13-letter words containing o, a, t, h, s
- on the parish — receiving parochial relief
- on the square — a rectangle having all four sides of equal length.
- onychophagist — the practice of biting one's nails, especially when done habitually and as a symptom of emotional disturbance.
- open and shut — immediately obvious upon consideration; easily decided: an open-and-shut case of murder.
- open-and-shut — immediately obvious upon consideration; easily decided: an open-and-shut case of murder.
- opisthobranch — any gastropod mollusk of the order Opisthobranchia, as the sea slugs, sea butterflies, and sea hares, characterized by a vestigial or absent mantle and shell and two pairs of tentacles.
- opisthography — the practice of writing on the front and back of a parchment or papyrus
- opthalmoscope — Misspelling of ophthalmoscope.
- optic chiasma — a site at the base of the forebrain where the inner half of the fibers of the left and right optic nerves cross to the opposite side of the brain.
- orchestra pit — musicians' seating in front of stage
- orchestra-pit — a group of performers on various musical instruments, including especially stringed instruments of the viol class, clarinets and flutes, cornets and trombones, drums, and cymbals, for playing music, as symphonies, operas, popular music, or other compositions.
- orchestralist — a person who writes or arranges orchestral music
- orchestrating — Present participle of orchestrate.
- orchestration — (uncountable) the arrangement of music for performance by an orchestra.
- orchestrators — Plural form of orchestrator.
- organ whistle — a steam or air whistle in which the jet is forced up against the thin edge of a pipe closed at the top.
- ornithischian — any herbivorous dinosaur of the order Ornithischia, having a pelvis resembling that of a bird. Compare saurischian.
- orthognathous — straight-jawed; having the profile of the face vertical or nearly so; having a gnathic index below 98.
- orthogonalise — to make (vectors, functions, etc.) orthogonal.
- orthographies — Plural form of orthography.
- orthosilicate — a silicate mineral
- ostreophagous — oyster-eating
- outwash plain — Geology. a broad, sloping landform built of coalesced deposits of outwash.
- overhastiness — the condition of being overhasty
- overhead-shot — over one's head; aloft; up in the air or sky, especially near the zenith: There was a cloud overhead.
- oystercatcher — any of several long-billed wading birds of the genus Haematopus that have chiefly black-and-white plumage and that feed on oysters, clams, mussels, etc.
- painted horse — paint (def 6).
- palos heights — a city in NE Illinois, near Chicago.
- pantheologist — a student of, or expert in, pantheology
- parasyntheton — a word formed by parasynthesis; for example, kind-hearted
- parnell shout — a social occasion where each person in a group pays for his or her own entertainment or meal
- parthenopaeus — a son of Hippomenes and Atalanta, and one of the Seven against Thebes.
- parthenospore — a spore developed without fertilization.
- parthian shot — a sharp, telling remark, act, gesture, etc., made in departing.
- pass the word — If you pass the word, you tell someone something that another person has told you.
- past historic — the simple past
- pathomorphism — abnormal morphology.
- pentadelphous — (of a plant) having its stamens arranged in five groups; (of stamens) being arranged in five groups
- pentastichous — (of plant leaves) arranged in five vertical rows
- petrophysical — relating to the analysis of the constitution and characteristics of rocks
- phantasmagory — phantasmagoria.
- phantom stock — an employee bonus expressed as the cash value of a specified amount of company stock to be received at a future date, meant to create employee interest in raising stock prices without giving any stock away.
- phelloplastic — an image or a representation that has been fashioned from cork
- phlogisticate — to integrate or blend phlogiston with
- phonocamptics — the branch of acoustics dealing with echoes
- phosphorylate — to introduce the phosphoryl group into (an organic compound).
- photo-sharing — the publishing of digital photographs on the internet
- photo-stating — a camera for making facsimile copies of documents, drawings, etc., in the form of paper negatives on which the positions of lines, objects, etc., in the originals are maintained.
- photoacoustic — optoacoustic
- photodynamics — the science dealing with light and its effects on living organisms.