12-letter words containing o, p, e, r
- office party — a party or informal social gathering for all the employees in a particular organization or department
- offset paper — paper used in a printing method in which the impression is made onto an intermediate surface, such as a rubber blanket, which transfers it to the paper
- offset press — a printing press used in the offset process, whereby a printing the impression is made onto an intermediate surface, such as a rubber blanket, which transfers it to the paper
- oil pressure — force that keeps engine lubricated
- oil producer — a country with reserves of oil
- oilseed rape — Oilseed rape is a plant with yellow flowers which is grown as a crop. Its seeds are crushed to make cooking oil.
- oligophrenia — less than normal mental development.
- oligophrenic — less than normal mental development.
- oligospermia — (medicine) Low volume of semen.
- ombudsperson — ombudsman (def 2).
- omnipresence — present everywhere at the same time: the omnipresent God.
- on principle — an accepted or professed rule of action or conduct: a person of good moral principles.
- on the prowl — to rove or go about stealthily, as in search of prey, something to steal, etc.
- on the ropes — a strong, thick line or cord, commonly one composed of twisted or braided strands of hemp, flax, or the like, or of wire or other material.
- oophorectomy — the operation of removing one or both ovaries; ovariectomy.
- open circuit — a discontinuous circuit through which no current can flow.
- open cluster — a comparatively young, irregularly shaped group of stars, often numbering up to several hundred, and held together by mutual gravitation; usually found along the central plane of the Milky Way and other galaxies.
- open primary — a direct primary election in which voters need not meet a test of party membership.
- open slather — to spread or apply thickly: to slather butter on toast.
- open texture — the failure of natural languages to determine future usage, particularly the ability of predicates to permit the construction of borderline cases
- open trailer — any dog that barks or bays on the trail of its quarry.
- open verdict — law: coroner's jury finding
- open-hearted — unreserved, candid, or frank: open-hearted advice.
- opera bouffe — a comic opera, especially of farcical character.
- opera singer — a professional singer of opera
- opera window — a narrow, fixed window on each side of the rear passenger compartment of an automobile.
- operatically — of or relating to opera: operatic music.
- operationism — the doctrine that the meaning of a scientific term, concept, or proposition consists of the operation or operations performed in defining or demonstrating it.
- operatorless — Without an operator (person who operates); fully automatic.
- operatorship — (in the oil and gas industries) the right to operate a well, field, or other oil source.
- opinionnaire — A form containing a list of statements, each of which the members of a selected group are asked to endorse or reject; the purpose being to gather information for a survey.
- oppressional — Exhibiting or relating to oppression.
- oppressively — burdensome, unjustly harsh, or tyrannical: an oppressive king; oppressive laws.
- optic center — a point about ten percent above the exact center of a printed page or layout.
- optical grep — vgrep
- optometrical — the practice or profession of examining the eyes, by means of suitable instruments or appliances, for defects in vision and eye disorders in order to prescribe corrective lenses or other appropriate treatment.
- optometrists — Plural form of optometrist.
- orange pekoe — a black tea composed of the smallest top leaves and grown in India and Ceylon.
- ordered pair — Mathematics. two quantities written in such a way as to indicate that one quantity precedes or is to be considered before the other, as (3, 4) indicates the Cartesian coordinates of a point in the plane.
- oregon grape — an evergreen shrub, Mahonia aquifolium, of the barberry family, of the western coast of the U.S., having small blue berries and yellow flowers that are the state flower of Oregon.
- oreopithecus — a genus of fossil primate from the Miocene coal deposits of Italy, formerly considered to be a possible hominid.
- organoleptic — perceived by a sense organ.
- ornithopters — Plural form of ornithopter.
- oropharynxes — Plural form of oropharynx.
- orthographer — a person versed in orthography or spelling.
- orthopaedics — (used with a singular verb) the medical specialty concerned with correction of deformities or functional impairments of the skeletal system, especially the extremities and the spine, and associated structures, as muscles and ligaments.
- orthopaedist — Alternative spelling of orthopedist.
- orthopedical — (American spelling) Alternative form of orthopaedical.
- orthopterans — Plural form of orthopteran.
- orthopterist — someone who studies the Orthoptera