21-letter words containing r, o, f, d, e, c
- law of thermodynamics — any of three principles variously stated in equivalent forms, being the principle that the change of energy of a thermodynamic system is equal to the heat transferred minus the work done (first law of thermodynamics) the principle that no cyclic process is possible in which heat is absorbed from a reservoir at a single temperature and converted completely into mechanical work (second law of thermodynamics) and the principle that it is impossible to reduce the temperature of a system to absolute zero in a finite number of operations (third law of thermodynamics)
- mayor of casterbridge — a novel (1886) by Thomas Hardy.
- mother-of-pearl cloud — nacreous cloud.
- pathfinder prospectus — a prospectus regarding the flotation of a new company that contains only sufficient details to test the market reaction
- performance indicator — a quantitative or qualitative measurement, or any other criterion, by which the performance, efficiency, achievement, etc of a person or organization can be assessed, often by comparison with an agreed standard or target
- peroxydisulfuric acid — persulfuric acid (def 2).
- piero della francesca — Piero della [pee-air-oh del-uh;; Italian pye-raw del-lah] /piˈɛər oʊ ˈdɛl ə;; Italian ˈpyɛ rɔ ˈdɛl lɑ/ (Show IPA), (Piero dei Franceschi) c1420–92, Italian painter.
- place of safety order — (in Britain) under the Children and Young Persons Act 1969, an order granted by a justice to a person or agency granting authority to detain a child or young person and take him or her to a place of safety for not more than 28 days, because of the child's actual or likely ill-treatment or neglect, etc
- prefect of discipline — a senior master in a Jesuit school or college
- purple-fringed orchid — either of two orchids, Habenaria fimbriata or H. psycodes, of eastern North America, having a cluster of fragrant purple flowers with a fringed lip.
- purple-fringed orchis — either of two North American orchids (Habenaria psycodes and H. fimbriata) with purple-fringed flowers
- radius of convergence — a positive number so related to a given power series that the power series converges for every number whose absolute value is less than this particular number.
- record of achievement — a statement of the personal and educational development of each pupil
- road traffic accident — an accident involving vehicles
- rutherford scattering — the scattering of an alpha particle through a large angle with respect to the original direction of motion of the particle, caused by an atom (Rutherford atom) with most of the mass and all of the positive electric charge concentrated at a center or nucleus.
- school of the soldier — an institution where instruction is given, especially to persons under college age: The children are at school.
- silicon tetrafluoride — a colorless, fuming gas, SiF 4 , used chiefly in the manufacture of fluosilicic acid.
- stockholder of record — a stockholder or his or her agent whose name is registered on the books of the issuing corporation at the close of a business day set for determining that stockholders shall receive dividends or vote on an issue.
- surface friction drag — the part of the drag on a body moving through a fluid that is dependent on the nature of the surface of the body
- surface-to-underwater — (of a missile, message, etc.) traveling from the surface of the earth to a target underwater.
- synchronized shifting — gear shifting in which the gears to be meshed are made to rotate at the same speed.
- the fall of the cards — the chance distribution of cards in a given deal
- tide-generating force — the difference between the force of gravity exerted by the moon or the sun on a particle of water in the ocean and that exerted on an equal mass of matter at the centre of the earth. The lunar tide-generating forces are about 2.2 times greater than are the solar ones
- universe of discourse — the totality of known or supposed objects and phenomena throughout space; the cosmos; macrocosm.
- university of iceland — (body, education) The Home of Fjolnir.