21-letter words containing o, p, e, n, d, r
- purple-fringed orchis — either of two North American orchids (Habenaria psycodes and H. fimbriata) with purple-fringed flowers
- pyrenean mountain dog — a large heavily built dog of an ancient breed originally used to protect sheep from wild animals: it has a long thick white coat with a dense ruff
- reading comprehension — a text that students use to help them improve their reading skills, by reading it and answering questions relating to the text. Sometimes used as a test or examination of reading skills. A reading comprehension can be in the student's own or another language
- redevelopment company — a private corporation or a public agency that stimulates the improvement of land, as through a building project subject to certain designs and controls, by financing, selling, or leasing such real estate to interested buyers or lessees.
- redwood national park — a national park in N California: redwood forest with some of the world's tallest trees. 172 sq. mi. (445 sq. km).
- residual unemployment — the unemployment that remains in periods of full employment, as a result of those mentally, physically, or emotionally unfit to work
- round-necked pullover — a sweater with a plain round neckline
- sanitation department — the department of local government responsible for collecting and disposing of refuse
- sao bernardo do campo — a city in SE Brazil, SE of São Paulo.
- sao tome and principe — Democratic Republic of, a republic in W Africa, comprising the islands of São Tomé and Príncipe, in the Gulf of Guinea, N of the equator: a former overseas province of Portugal; gained independence in 1975. 372 sq. mi. (964 sq. km). Capital: São Tomé.
- school superintendent — an official whose job is to oversee school administration within a district
- science correspondent — a newspaper or television journalist who specializes in reporting on new discoveries in science
- sheppard's correction — a method of correcting the bias in standard deviations and higher moments of distributions that arises from grouping values of the variable.
- sinusoidal projection — an equal-area projection in which parallels are straight lines spaced at regular intervals, the central meridian is a straight line one-half the length of the equator, and the other meridians are curves symmetrical to the central meridian.
- skop, skiet en donder — violent action and melodramatic adventure in a film
- special correspondent — a journalist who covers stories firsthand from a war zone
- spherical coordinates — Usually, spherical coordinates. any of three coordinates used to locate a point in space by the length of its radius vector and the angles this vector makes with two perpendicular polar planes.
- steady-state response — A steady-state response is the behavior of a circuit after a long time when steady conditions have been reached after an external excitation.
- step-down transformer — a device that transfers an alternating current from one circuit to one or more other circuits with a decrease of voltage
- stock list department — (in an American stock exchange) the department dealing with monitoring compliance with its listing requirements and rules
- student participation — the extent to which students participate or involve themselves in a class, course, etc
- the end of one's rope — the end of one's endurance, resources, etc.
- the oldest profession — prostitution
- thermal decomposition — Thermal decomposition is the process in which a chemical species breaks down when its temperature is increased.
- up close and personal — face to face, intimately
- wet collodion process — a photographic process, in common use in the mid-19th century, employing a glass photographic plate coated with iodized collodion and dipped in a silver nitrate solution immediately before use.
- whip-and-tongue graft — a graft prepared by cutting both the scion and the stock in a sloping direction and inserting a tongue in the scion into a slit in the stock.
- white-crowned sparrow — a North American sparrow, Zonotrichia leucophrys, having black and white stripes on the head.
- wholesale price index — an indicator of price changes in the wholesale market
- xeroderma pigmentosum — a rare inherited disease characterized by sensitivity to ultraviolet light, exposure resulting in lesions and tumors of the skin and eyes.