obloquial
Of or relating to obloquy.

oblyrate
Having a reverse lyrate shape, with the lobes near the apex.

obmutescent
Silent; unable or refusing to speak.

oboelike
Resembling or characteristic of an oboe.

oboval
obovate

obovate
Shaped like an egg, with the broad extremity located away from the base.

obovoid
Approximately obovate in shape.

obovoidal
obovoid

obovoids
plural of obovoid

obpandurate
Having a reverse pandurate shape, with the sinuosity toward the apex and the broadest part toward the base.

obpyramid
A pyramid with the apex downward; an inverse pyramid.

obpyramidal
Pyramidal, but having the apex downward; inversely pyramidal.

obpyriform
Having a shape that is in outline like that of a pear, with the base at the narrower end.

obreniform
Having a reverse reniform shape, with the petiole opposite the notch.

obreptitious
Done or obtained by surprise, with secrecy, or by concealment of the truth.

obsagittate
Of a reverse sagittate shape, with two pointed lobes extending at the apex.

obscener
comparative form of obscene: more obscene

obscenest
superlative form of obscene: most obscene

obscurable
Which can be obscured.

obscurantic
Employing obscurantism.

obscurantist
A practitioner of obscurantism; an obscurant.

obscurantistic
Of or relating to obscurantism.

obscurantists
plural of obscurantist

obscurative
Tending to obscure; making something unclear or abstruse.

obscurer
comparative form of obscure: more obscure

obscurers
plural of obscurer

obscurest
superlative form of obscure: most obscure

obsequial
Relating to an obsequy or funeral rite.

observable
Able to be observed.
Deserving to be observed; worth regarding; remarkable.

observant
Alert and paying close attention; watchful.
Diligently attentive in observing a law, custom, duty or principle; regardful; mindful.
Practicing a religion.

observational
Relating to observation, especially scientific observation.

observatorial
Relating to an observatory.
Relating to an observator or observer.

observerless
Without observers.

obsessional
Marked by obsession

obsessive
Prone to cause obsession.
Having one thought or pursuing one activity to the absolute or nearly absolute exclusion of all others.
Excessive, as results from obsession.

obsessoid
Showing resemblance to obsessive-compulsive disorder.

obsidian
A type of naturally occurring black glass produced by volcanoes.
A slightly bluish black, the color of obsidian glass.

obsidional
Pertaining to a siege.

obsidionary
obsidional; relating to a siege

obsidious
besieging; besetting, obsessional

obstacular
Being or relating to an obstacle.

obstetric
Of or relating to obstetrics (the care of women during and after pregnancy).

obstetrical
Alternative form of obstetric.

obstinacious
obstinate

obstinant
Obstinate.

obstinate
Stubbornly adhering to an opinion, purpose, or course, usually with implied unreasonableness; persistent.
Not easily subdued or removed.
Typical of an obstinate person; fixed and unmoving.

obstinent
Misspelling of obstinant.

obstipational
Of or relating to obstipation.

obstractive
Misspelling of obstructive.

obstrepalous
obstreperous

obstreperous
Attended by, or making, a loud and tumultuous noise; boisterous.
Stubbornly defiant; disobedient; resistant to authority or control (whether in a noisy manner or not).

obstructable
Able to be obstructed.

obstructible
Alternative form of obstructable.

obstructional
Being or relating to an obstruction.

obstructionist
Someone who systematically obstructs the actions of others.
Someone who systematically obstructs the actions of others.

obstructionistic
Relating to, or supporting, obstructionism.

obstructive
Causing obstructions.

obstruent
Causing obstruction; blocking up.

obstruents
plural of obstruent

obstruse
Abstruse.

obstruser
comparative form of obstruse: more obstruse

obstrusest
superlative form of obstruse: most obstruse

obstrusive
Misspelling of obtrusive.

obtainable
Able to be obtained.

obtect
Having the legs and other appendages more or less strongly cemented to the body.

obtrapeziform
trapeziform, but attached by the narrower trapezoidal base

obtriangular
triangular with the apex downwards

obtrullate
In the form of a reversed trowel (with longer sides meeting at the base)

obturacular
Relating to the obturaculum

obturational
Of or relating to obturation.

obturative
Relating to or causing obturation

obturbinate
inversely top-shaped

obtusangular
obtuse-angled

obtusish
Somewhat obtuse.

obumbrant
overhanging

obverse
Turned or facing toward the observer.
Corresponding; complementary.
Having the base, or end next to the attachment, narrower than the top.

obverses
plural of obverse

obvi
Clipping of obvious.

obviable
Capable of being obviated.

obviate
To anticipate and prevent or bypass (something which would otherwise have been necessary or required); to render (something) unnecessary.
To avoid (a future problem or difficult situation).

obviative
A grammatical marker that distinguishes a relatively non-salient referent in a given context from a relatively salient (proximate) one.

obviatives
plural of obviative

obvious
Easily discovered, seen, or understood; self-explanatory.

obvoid
Egg-shaped and solid, with the narrow end at the base.

obvolute
overlapping; contorted; convoluted
Having two opposite leaves, each with one edge overlapping the nearest edge of the other.
Having a circle of several leaves or petals which overlap in that manner.

obvoluted
Alternative form of obvolute.

obvy
Alternative form of obvi (“obviously”).

obzocky
Awkward; unattractive; out of place; lopsided; misshapen.

oc
Initialism of of course.

occ
Clipping of occupational.

occasional
Occurring or appearing irregularly from time to time, but not often; incidental.
Created for a specific occasion.
Intended for use as the occasion requires.
Acting in the indicated role from time to time.

occasionalistic
Of or relating to the doctrine of occasionalism.

occasionless
Without occasion.

occidental
Of, pertaining to, or situated in, the occident, or west; western.
Of a gem or precious stone: of inferior value or quality.

occidentals
plural of occidental

occiduous
Western; occidental.

occipital
Of, pertaining to, or located within or near the occiput (back of the head) or the occipital bone.

occipitalised
Modified by occipitalisation

occipitalized
Alternative form of occipitalised.

occipitals
plural of occipital

occipitoanterior
Having the occiput facing anteriorly or anterolaterally.

occipitoatlantal
Relating to the occiput and the atlas.

occipitoatlantoaxial
Relating to the articulation of the occiput and atlas with the axis.

occipitoatloid
Relating to, or connecting the occipital bone and the atlas

occipitoaxial
Of or pertaining to the occipital bone and second vertebra, or axis.

occipitobregmatic
Of or relating to the occiput and the bregma.

occipitocervical
Relating to the occiput and the neck.

occipitocortical
Relating to the occiput and the cerebral cortex

occipitocranial
Relating to the occiput and the cranium

occipitofacial
Of or relating to the occiput and the face.

occipitofrontal
Of or pertaining to the occipital and frontal bones of the skull.
Of or pertaining to the occipitofrontalis muscle.

occipitoiliac
Of or relating to the occiput and the ilium.

occipitolateral
Having the occiput facing laterally.

occipitomastoid
Relating to, or connecting the occipital and mastoid bones

occipitomental
Of or relating to (the distance between) the chin and the occiput.

occipitonasal
Relating to, or between, the occipital bone and the nose

occipitonuchal
Of or relating to the occiput and the back of the neck.

occipitoparietal
Relating to the occipital and the parietal bones

occipitoparietotemporal
Synonym of parietooccipitotemporal.

occipitopontine
occipital and pontine

occipitoposterior
Having the occiput facing posteriorly or posterolaterally.

occipitosacral
occipital and sacral