12 letter words starting with O
Twelve letter words starting with the O are helpful when playing a game like Wordfeud or Scrabble. We have a complete list of dictionary words starting with the letter O.
- oafishnesses
- oarsmanships
- obdurateness
- obfuscations
- objectifying
- objectivisms
- objectivists
- objurgations
- oblanceolate
- oblatenesses
- obligatorily
- obligingness
- obliterating
- obliteration
- obliterative
- obliterators
- obnubilating
- obnubilation
- obscurantism
- obscurantist
- obscurations
- obsequiously
- observations
- obsolescence
- obsoleteness
- obstetrician
- obstreperous
- obstructions
- obstructives
- obtusenesses
- occasionally
- occidentally
- occultations
- occupational
- oceanography
- oceanologies
- oceanologist
- ochlocracies
- octahedrally
- octapeptides
- octogenarian
- octosyllabic
- octosyllable
- odiousnesses
- odontoblasts
- officeholder
- officialdoms
- officialeses
- officialisms
- officiations
- offishnesses
- offscourings
- oleaginously
- oleandomycin
- oleoresinous
- olfactometer
- oligarchical
- oligochaetes
- oligophagies
- oligophagous
- oligopsonies
- oligotrophic
- omnipotences
- omnipotently
- omnipresence
- omnisciences
- omnisciently
- omnivorously
- oncogenicity
- oncornavirus
- onomastician
- onomatopoeia
- onomatopoeic
- onychophoran
- oophorectomy
- opalescences
- opalescently
- opaquenesses
- openhandedly
- operatically
- operationism
- operationist
- operatorless
- opinionative
- opportunisms
- opportunists
- opposability
- oppositeness
- oppositional
- oppressively
- optimalities
- optimisation
- optimization
- optometrists
- oratorically
- orchestrally
- orchestrated
- orchestrater
- orchestrates
- orchestrator
- orchidaceous
- ordinariness
- organicities
- organisation
- organization
- organoleptic
- organologies
- orientalisms
- orientalists
- orientalized
- orientalizes
- orientations
- orienteering
- originations
- orismologies
- ornamentally
- ornatenesses
- ornerinesses
- ornithologic
- ornithopters
- orographical
- oropharynges
- oropharynxes
- orotundities
- orthocenters
- orthodontias
- orthodontics
- orthodontist
- orthogeneses
- orthogenesis
- orthogenetic
- orthogonally
- orthographic
- orthopaedics
- orthopedists
- orthopterans
- orthopterist
- orthopteroid
- orthorhombic
- orthotropous
- oscillations
- oscillograms
- oscillograph
- oscilloscope
- osmolalities
- osmolarities
- ossification
- ostentations
- ostentatious
- osteoblastic
- osteoclastic
- osteogeneses
- osteogenesis
- osteological
- osteologists
- osteomalacia
- osteopathies
- osteoplastic
- osteoporoses
- osteoporosis
- osteoporotic
- osteosarcoma
- ostracoderms
- otherworldly
- otiosenesses
- otoscleroses
- otosclerosis
- outachieving
- outbalancing
- outbargained
- outbrazening
- outbreedings
- outbuildings
- outcavilling
- outcompeting
- outcroppings
- outdatedness
- outdelivered
- outdesigning
- outdistanced
- outdistances
- outgalloping
- outgeneraled
- outglittered
- outgoingness
- outintrigued
- outintrigues
- outjockeying
- outlandishly
- outmaneuvers
- outmastering
- outnumbering
- outorganized
- outorganizes
- outperformed
- outplacement
- outpoliticks
- outpopulated
- outpopulates
- outpreaching
- outproducing
- outpromising
- outrageously
- outreasoning
- outrebounded
- outreckoning
- outreproduce
- outrivalling
- outscreaming
- outsiderness
- outsourcings
- outsparkling
- outspreading
- outspringing
- outsprinting
- outstretched
- outstretches
- outstripping
- outthrobbing
- outthrusting
- outtraveling
- outtravelled
- outwrestling
- ovariotomies
- overabstract
- overabundant
- overachieved
- overachiever
- overachieves
- overactivity
- overanalyses
- overanalysis
- overanalyzed
- overanalyzes
- overarousals
- overarranged
- overarranges
- overasserted
- overbalanced
- overbalances
- overbleached
- overbleaches
- overborrowed
- overbreeding
- overbriefing
- overbrowsing
- overbuilding
- overburdened
- overcapacity
- overcastings
- overcautions
- overcautious
- overcharging
- overchilling
- overclaiming
- overclassify
- overcleaning
- overclearing
- overclouding
- overcoaching
- overcoloring
- overcompress
- overconcerns
- overconsumed
- overconsumes
- overcontrols
- overcorrects
- overcounting
- overcramming
- overcritical
- overcropping
- overcrowding
- overdecorate
- overdesigned
- overdevelops
- overdirected
- overdiscount
- overdocument
- overdominant
- overdramatic
- overdressing
- overdrinking
- overeducated
- overeducates
- overemphases
- overemphasis
- overemphatic
- overenamored
- overengineer
- overenrolled
- overequipped
- overestimate
- overexciting
- overexercise
- overexerting
- overexertion
- overexpanded
- overexplains
- overexplicit
- overexploits
- overexposing
- overexposure
- overextended
- overfamiliar
- overfatigued
- overfatigues
- overfavoring
- overflooding
- overfocusing
- overfocussed
- overfocusses
- overfulfills
- overgarments
- overgenerous
- overgoverned
- overhandling
- overharvests
- overhonoring
- overhuntings
- overidealize
- overidentify
- overindulged
- overindulges
- overinflated
- overinflates
- overinformed
- overissuance
- overlaboring
- overlearning
- overlengthen
- overlighting
- overliterary
- overlordship
- overmanaging
- overmannered
- overmastered
- overmatching
- overmaturity
- overmedicate
- overmodestly
- overnighters
- overnighting
- overoperated
- overoperates
- overoptimism
- overoptimist
- overorganize
- overornament
- overpackaged
- overpackages
- overpayments
- overpedaling
- overpedalled
- overpeopling
- overpersuade
- overplanning
- overplanting
- overplotting
- overpopulate
- overpowering
- overpraising
- overpressure
- overprinting
- overproduced
- overproduces
- overprograms
- overpromised
- overpromises
- overpromoted
- overpromotes
- overprotects
- overreachers
- overreaching
- overreacting
- overreaction
- overregulate
- overreliance
- overreported
- overresponds
- overroasting
- oversanguine
- oversaturate
- overserviced
- overservices
- overshadowed
- overshooting
- oversimplify
- overslaughed
- oversleeping
- overslipping
- overspenders
- overspending
- overspilling
- overstaffing
- oversteering
- overstepping
- overstirring
- overstocking
- overstrained
- overstressed
- overstresses
- overstrewing
- overstridden
- overstriding
- overstudying
- overstuffing
- oversupplied
- oversupplies
- oversweetens
- overswinging
- overtaxation
- overteaching
- overthinking
- overthrowing
- overtightens
- overtraining
- overtreating
- overtrimming
- overtrumping
- overutilized
- overutilizes
- overvoltages
- overwatching
- overwatering
- overwearying
- overweighing
- overweighted
- overwhelming
- overwintered
- overwithheld
- overwithhold
- ovipositions
- owlishnesses
- oxalacetates
- oxaloacetate
- oxyacetylene
- oxygenations
- ozonizations
- ozonospheres
- oafishnesses
- oarsmanships
- obcompressed
- obdurateness
- obedientiary
- obfuscations
- objectifying
- objectivated
- objectivates
- objectivised
- objectivises
- objectivisms
- objectivists
- objectivized
- objectivizes
- objurgations
- oblanceolate
- oblatenesses
- obligational
- obligatorily
- obligingness
- obliquations
- obliterating
- obliteration
- obliterative
- obliterators
- obliviscence
- obmutescence
- obnubilating
- obnubilation
- obreptitious
- obscurantism
- obscurantist
- obscurations
- obscurements
- obsecrations
- obsequiously
- observancies
- observations
- obsessionist
- obsignations
- obsolescence
- obsoleteness
- obstetrician
- obstipations
- obstreperate
- obstreperous
- obstrictions
- obstropalous
- obstropulous
- obstructions
- obstructives
- obtemperated
- obtemperates
- obtestations
- obtruncating
- obtusenesses
- obumbrations
- occasionally
- occidentally
- occultations
- occultnesses
- occupational
- oceanography
- oceanologies
- oceanologist
- ochlocracies
- ochlophobiac
- ochlophobias
- ochroleucous
- octahedrally
- octahedrites
- octapeptides
- octaploidies
- octastichons
- octastichous
- octastrophic
- octillionths
- octogenarian
- octogenaries
- octopetalous
- octosepalous
- octostichous
- octosyllabic
- octosyllable
- octuplicates
- odiousnesses
- odontoblasts
- odontogenies
- odontographs
- odontography
- odontologies
- odontologist
- odontomatous
- odontophobia
- odontophoral
- odontophoran
- odontophores
- odorimetries
- oenophilists
- oesophagitis
- offendresses
- officeholder
- officialdoms
- officialeses
- officialisms
- officialties
- officiations
- offishnesses
- offscourings
- oleaginously
- oleandomycin
- oleographies
- oleomargarin
- oleoresinous
- olfactometer
- olfactometry
- olfactronics
- oligarchical
- oligochaetes
- oligochromes
- oligopeptide
- oligophagies
- oligophagous
- oligopsonies
- oligospermia
- oligotrophic
- ombrophilous
- ombrophobous
- omissiveness
- ommatophores
- omnificences
- omniparities
- omnipotences
- omnipotently
- omnipresence
- omnisciences
- omnisciently
- omnivorously
- omphalomancy
- oncogenicity
- oncornavirus
- oneirocritic
- oneirodynias
- oneirologies
- oneiromancer
- onomasiology
- onomastician
- onomasticons
- onomatopoeia
- onomatopoeic
- onychophoran
- oophorectomy
- oophoritises
- opalescences
- opalescently
- opaquenesses
- opeidoscopes
- openhandedly
- operatically
- operationism
- operationist
- operatorless
- ophicalcites
- ophidiariums
- ophiolatries
- ophiolatrous
- ophiological
- ophiologists
- ophiomorphic
- ophiophagous
- ophiophilist
- ophthalmists
- ophthalmitis
- opinionately
- opinionative
- opinionators
- opisthodomoi
- opisthodomos
- opisthograph
- opisthotonic
- opisthotonos
- opotherapies
- oppignerated
- oppignerates
- oppignorated
- oppignorates
- opportunisms
- opportunists
- opposability
- oppositeness
- oppositional
- oppressingly
- oppressively
- oppugnancies
- opsonisation
- opsonization
- optimalising
- optimalities
- optimalizing
- optimisation
- optimistical
- optimization
- optoacoustic
- optometrical
- optometrists
- oracularness
- oratorically
- orbicularity
- orchestrally
- orchestrated
- orchestrater
- orchestrates
- orchestrator
- orchestrinas
- orchestrions
- orchidaceous
- orchidectomy
- orchidomania
- ordinariness
- oreographies
- orepearching
- organicistic
- organicities
- organisation
- organismally
- organistrums
- organization
- organogenies
- organography
- organoleptic
- organologies
- organologist
- orichalceous
- orientalised
- orientalises
- orientalisms
- orientalists
- orientalized
- orientalizes
- orientations
- orienteering
- originations
- orismologies
- ornamentally
- ornamentists
- ornatenesses
- ornerinesses
- ornithogalum
- ornithologic
- ornithomancy
- ornithomorph
- ornithophily
- ornithopters
- ornithosaurs
- ornithoscopy
- orogenically
- orographical
- orologically
- oropharynges
- oropharynxes
- ororotundity
- orotundities
- orthoborates
- orthocenters
- orthocentres
- orthocephaly
- orthocousins
- orthodontias
- orthodontics
- orthodontist
- orthodromics
- orthodromies
- orthogeneses
- orthogenesis
- orthogenetic
- orthognathic
- orthogonally
- orthographer
- orthographic
- orthomorphic
- orthopaedics
- orthopaedies
- orthopaedist
- orthopedical
- orthopedists
- orthopraxies
- orthopterans
- orthopterist
- orthopteroid
- orthopterous
- orthorhombic
- orthotoneses
- orthotonesis
- orthotropies
- orthotropism
- orthotropous
- orthovanadic
- oryctologies
- oscillations
- oscillograms
- oscillograph
- oscilloscope
- osculatories
- osmolalities
- osmolarities
- ossification
- osteichthyan
- ostentations
- ostentatious
- osteoblastic
- osteoclastic
- osteodermous
- osteogeneses
- osteogenesis
- osteogenetic
- osteological
- osteologists
- osteomalacia
- osteomalacic
- osteopathies
- osteopathist
- osteoplastic
- osteoporoses
- osteoporosis
- osteoporotic
- osteosarcoma
- ostracisable
- ostracizable
- ostracoderms
- ostreophages
- otherworldly
- otiosenesses
- otoscleroses
- otosclerosis
- outachieving
- outbalancing
- outbargained
- outblustered
- outbrazening
- outbreathing
- outbreedings
- outbuildings
- outcavilling
- outcompeting
- outcraftying
- outcroppings
- outcrossings
- outdatedness
- outdelivered
- outdesigning
- outdistanced
- outdistances
- outercourses
- outfangthief
- outgalloping
- outgeneraled
- outglittered
- outgoingness
- outintrigued
- outintrigues
- outjockeying
- outlandishly
- outlaunching
- outmaneuvers
- outmanoeuvre
- outmarriages
- outmastering
- outmeasuring
- outmodedness
- outnumbering
- outorganised
- outorganises
- outorganized
- outorganizes
- outpassioned
- outperformed
- outplacement
- outpoliticks
- outpopulated
- outpopulates
- outpreaching
- outproducing
- outpromising
- outrageously
- outreasoning
- outrebounded
- outreckoning
- outreddening
- outreproduce
- outrivalling
- outscreaming
- outsiderness
- outsourcings
- outsparkling
- outspreading
- outspringing
- outsprinting
- outstraining
- outstretched
- outstretches
- outstripping
- outsweetened
- outthrobbing
- outthrusting
- outtraveling
- outtravelled
- outvillained
- outwrestling
- ovariotomies
- ovariotomist
- overabounded
- overabstract
- overabundant
- overachieved
- overachiever
- overachieves
- overactivity
- overanalysed
- overanalyses
- overanalysis
- overanalyzed
- overanalyzes
- overarousals
- overarranged
- overarranges
- overasserted
- overbalanced
- overbalances
- overbiddings
- overblankets
- overbleached
- overbleaches
- overborrowed
- overbounding
- overbreeding
- overbridging
- overbriefing
- overbrimming
- overbrowsing
- overbuilding
- overburdened
- overburthens
- overcanopied
- overcanopies
- overcapacity
- overcarrying
- overcastings
- overcatching
- overcautions
- overcautious
- overcharging
- overchilling
- overclaiming
- overclassify
- overcleaning
- overclearing
- overclouding
- overcoaching
- overcoatings
- overcoloring
- overcoloured
- overcompress
- overconcerns
- overconsumed
- overconsumes
- overcontrols
- overcorrects
- overcounting
- overcovering
- overcramming
- overcritical
- overcropping
- overcrowding
- overdecorate
- overdesigned
- overdevelops
- overdeviated
- overdeviates
- overdirected
- overdiscount
- overdocument
- overdominant
- overdramatic
- overdraughts
- overdressing
- overdrinking
- overeducated
- overeducates
- overemphases
- overemphasis
- overemphatic
- overenamored
- overengineer
- overenrolled
- overequipped
- overestimate
- overexciting
- overexercise
- overexerting
- overexertion
- overexpanded
- overexplains
- overexplicit
- overexploits
- overexposing
- overexposure
- overextended
- overfamiliar
- overfatigued
- overfatigues
- overfavoring
- overfineness
- overfinished
- overflooding
- overflourish
- overflowings
- overfocusing
- overfocussed
- overfocusses
- overfondness
- overfreedoms
- overfreights
- overfulfills
- overfullness
- overfundings
- overgarments
- overgenerous
- overglancing
- overglooming
- overgoverned
- overgrainers
- overgraining
- overgrassing
- overgrazings
- overgreening
- overhandling
- overharvests
- overheatings
- overhonoring
- overhuntings
- overidealise
- overidealize
- overidentify
- overinclined
- overindulged
- overindulges
- overinflated
- overinflates
- overinformed
- overinsuring
- overissuance
- overkindness
- overlaboring
- overlaboured
- overlaunched
- overlaunches
- overlearning
- overleathers
- overleavened
- overlengthen
- overlighting
- overliterary
- overlockings
- overlordship
- overmanaging
- overmannered
- overmastered
- overmatching
- overmaturity
- overmeasured
- overmeasures
- overmedicate
- overmodestly
- overmounting
- overmultiply
- overniceness
- overnighters
- overnighting
- overofficing
- overoperated
- overoperates
- overoptimism
- overoptimist
- overorganise
- overorganize
- overornament
- overpackaged
- overpackages
- overpainting
- overpayments
- overpedaling
- overpedalled
- overpeopling
- overperching
- overpersuade
- overpictured
- overpictures
- overpitching
- overplanning
- overplanting
- overplotting
- overpopulate
- overpowering
- overpraising
- overprepared
- overprepares
- overpressing
- overpressure
- overprinting
- overproduced
- overproduces
- overprograms
- overpromised
- overpromises
- overpromoted
- overpromotes
- overprotects
- overrashness
- overreachers
- overreaching
- overreacting
- overreaction
- overreckoned
- overrefining
- overregulate
- overreliance
- overreported
- overresponds
- overripeness
- overripening
- overroasting
- oversanguine
- oversaturate
- overschutcht
- overscutched
- overserviced
- overservices
- overshadowed
- overshooting
- overshowered
- oversimplify
- overskipping
- overslaughed
- oversleeping
- overslipping
- overspenders
- overspending
- overspilling
- overstaffing
- overstaining
- overstanding
- oversteering
- overstepping
- overstinking
- overstirring
- overstocking
- overstrained
- overstressed
- overstresses
- overstrewing
- overstridden
- overstriding
- overstriking
- overstudying
- overstuffing
- oversubtlety
- oversupplied
- oversupplies
- overswearing
- oversweetens
- overswelling
- overswimming
- overswinging
- overtaxation
- overteaching
- overthinking
- overthrowers
- overthrowing
- overthwarted
- overtightens
- overtowering
- overtraining
- overtreating
- overtrimming
- overtripping
- overtrumping
- overtrusting
- overutilised
- overutilises
- overutilized
- overutilizes
- overvoltages
- overwatching
- overwatering
- overwearying
- overweathers
- overweenings
- overweighing
- overweighted
- overwhelming
- overwintered
- overwithheld
- overwithhold
- overwresting
- overwrestled
- overwrestles
- ovipositions
- owlishnesses
- oxalacetates
- oxaloacetate
- oxidimetries
- oxidisations
- oxidizations
- oxyacetylene
- oxycephalies
- oxycephalous
- oxygenations
- oxysulphides
- ozonisations
- ozonizations
- ozonospheres