20-letter words containing l, f, r
- patent foramen ovale — a congenital heart defect resulting from failure of the foramen ovale to close shortly after birth.
- paternal grandfather — the father of someone's father
- period of revolution — a rather large interval of time that is meaningful in the life of a person, in history, etc., because of its particular characteristics: a period of illness; a period of great profitability for a company; a period of social unrest in Germany.
- permonosulfuric acid — persulfuric acid (def 1).
- pest control officer — a person who gets rid of pests such as rats and mice
- photoelectric effect — the phenomenon in which the absorption of electromagnetic radiation, as light, of sufficiently high frequency by a surface, usually metallic, induces the emission of electrons from the surface.
- piezoelectric effect — the property exhibited by some nonconducting crystals of becoming electrically polarized when mechanically strained and of becoming mechanically strained when an electric field is applied.
- polymorphic function — a function in a computer program that can deal with a number of different types of data
- portfolio employment — the practice of working for several employers simultaneously rather than working full-time for a single employer
- post office protocol — (messaging, protocol) (POP) A protocol designed to allow single-user computers to retrieve electronic mail from a POP server via TCP/IP. The default port is 110. The POP server might be a computer with a permanent Internet connection whereas its clients might only connect to it occasionally, e.g. by modem. There are (in 1994) three versions: POP, POP2, and POP3. Later versions are NOT compatible with earlier ones.
- potential difference — voltage
- prefecture apostolic — a territory in the early stage of missionary development.
- probability function — the function the values of which are probabilities of the distinct outcomes of a discrete random variable
- public record office — an institution in which official records are stored and kept available for inspection by the public
- quantum field theory — any theory in which fields are treated by the methods of quantum mechanics; each field can then be regarded as consisting of particles of a particular kind, which may be created and annihilated.
- red mercuric sulfide — a crystalline, water-insoluble, poisonous compound, HgS, occurring as a coarse, black powder (black mercuric sulfide) or as a fine, bright-scarlet powder (red mercuric sulfide) used chiefly as a pigment and as a source of the free metal.
- reflecting telescope — an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope) consists essentially of an objective lens set into one end of a tube and an adjustable eyepiece or combination of lenses set into the other end of a tube that slides into the first and through which the enlarged object is viewed directly; the other form (reflecting telescope) has a concave mirror that gathers light from the object and focuses it into an adjustable eyepiece or combination of lenses through which the reflection of the object is enlarged and viewed. Compare radio telescope.
- refracting telescope — an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope) consists essentially of an objective lens set into one end of a tube and an adjustable eyepiece or combination of lenses set into the other end of a tube that slides into the first and through which the enlarged object is viewed directly; the other form (reflecting telescope) has a concave mirror that gathers light from the object and focuses it into an adjustable eyepiece or combination of lenses through which the reflection of the object is enlarged and viewed. Compare radio telescope.
- refuse disposal unit — a unit or part of a sink that disposes of waste food, etc, by grinding
- republic of maldives — a republic occupying an archipelago of 1087 coral islands in the Indian Ocean, southwest of Sri Lanka: came under British protection in 1887; became independent in 1965 and a republic in 1968; member of the Commonwealth (1982–2016). The economy and infrastructure were severely damaged in the Indian Ocean tsunami of December 2004. Official language: Divehi. Official religion: (Sunni) Muslim. Currency: rufiyaa. Capital: Malé. Pop: 393 988 (2013 est). Area: 298 sq km (115 sq miles)
- request for proposal — (programming) (RFP) The publication by a prospective software purchaser of details of the required system in order to attract offers by software developers to supply it. Software development under contract starts with the selection of the software developer by the customer. A request for proposal (also called in Britain an "invitation to tender") is the beginning of the selection process.
- ring of the nibelung — Richard Wagner's tetralogy of music dramas: Das Rheingold (completed 1869), Die Walküre (completed 1870), Siegfried (completed 1876), and Götterdämmerung (completed 1876): the cycle was first performed at Bayreuth, 1876.
- ring wall foundation — A ring wall foundation is a base made of concrete, used to put large tanks on.
- royal air force list — an official list of all serving commissioned officers of the RAF and reserve officers liable for recall
- sb's future lies swh — If you say that someone's future lies in a particular place or activity, you think they will be most successful or happy in that place or doing that activity.
- second earl of essex — 2nd Earl of, Devereux, Robert.
- self-differentiating — to form or mark differently from other such things; distinguish.
- sergeant first class — a noncommissioned officer ranking next above a staff sergeant and below a first or master sergeant.
- small craft advisory — a U.S. National Weather Service advisory of sustained winds, over coastal and inland waters, with speeds of 20–33 knots (23–38 mph, 10–17 m/sec). Regional NWS offices have discretion over the choice of the lower limit.
- snowflake generation — the generation of people who became adults in the 2010s, viewed as being less resilient and more prone to taking offence than previous generations
- snows of kilimanjaro — a short story (1936) by Ernest Hemingway.
- sodium fluoroacetate — a white, amorphous, water-soluble, poisonous powder, C 2 H 2 FO 2 Na, used as a rodenticide.
- software methodology — (programming) The study of how to navigate through each phase of the software process model (determining data, control, or uses hierarchies, partitioning functions, and allocating requirements) and how to represent phase products (structure charts, stimulus-response threads, and state transition diagrams).
- solitary confinement — the confinement of a prisoner in a cell or other place in which he or she is completely isolated from others.
- spiral of archimedes — a curve that is the locus of a point that moves outward with uniform speed along a vector, beginning at the origin, while the vector rotates about the origin with uniform angular velocity. Equation (in polar coordinates): r = aθ.
- split the difference — the state or relation of being different; dissimilarity: There is a great difference between the two.
- spread like wildfire — If something, especially news or a rumour, spreads like wildfire, it spreads extremely quickly.
- squirrel's-foot fern — ball fern.
- strike off the rolls — to expel from membership
- strong nuclear force — an interaction between elementary particles responsible for the forces between nucleons in the nucleus. It operates at distances less than about 10–15 metres, and is about a hundred times more powerful than the electromagnetic interaction
- the legal profession — the profession of law
- the luck of the draw — If you say that something is the luck of the draw, you mean that it is the result of chance and you cannot do anything about it.
- theory of relativity — relativity (def 2).
- there is no call for — If you say that there is no call for someone to behave in a particular way, you are criticizing their behaviour, usually because you think it is rude.
- theresa of avila, st — Saint. Also, Teresa. Also called Theresa of Avila [ah-vee-lah] /ˈɑ viˌlɑ/ (Show IPA), 1515–82, Spanish Carmelite nun, mystic, and writer.
- thomas of erceldoune — Thomas of, Thomas of Erceldoune.
- thorn in one's flesh — a sharp excrescence on a plant, especially a sharp-pointed aborted branch; spine; prickle.
- to burst into flames — If something bursts into flames or bursts into flame, it suddenly starts burning strongly.
- to come to full term — to be carried or last until the ninth month of gestation or pregnancy
- to fall on deaf ears — If a request falls on deaf ears or if the person to whom the request is made turns a deaf ear to it, they take no notice of it.