19-letter words containing c, l, e, f, r
- differential backup — (operating system) A kind of backup that copies all files that have changed since the last full backup. Each differential backup will include all files in previous differential backups since the full backup so to restore a version of a file, you only need to search the full backup and the relevant differential backup. Some systems support differential backup by associating an "Archive" flag with each file and setting this flag whenever the file is modified to indicate that it should be included in the next backup. A differential backup does not change this flag, whereas an incremental backup resets it.
- digital certificate — (communications, security) An attachment to an electronic mail message used for security purposes, e.g. to verify that a user sending a message is who he or she claims to be, and to provide the receiver with the means to encode a reply. An individual wishing to send an encrypted message applies for a digital certificate from a certificate authority (CA). The CA issues an encrypted digital certificate containing the applicant's public key and a variety of other identification information. The CA makes its own public key readily available on the Internet. The recipient of an encrypted message uses the CA's public key to decode the digital certificate attached to the message, verifies it as issued by the CA and then obtains the sender's public key and identification information held within the certificate.
- disciples of christ — a Christian denomination, founded in the U.S. by Alexander Campbell in the early part of the 19th century, that rejects all creeds, holds the Bible as a sufficient rule of faith and practice, administers baptism by immersion, celebrates the Lord's Supper every Sunday, and has a congregational polity.
- effervescent tablet — Effervescent tablets break down quickly when they are dropped into water or another liquid.
- elastic deformation — In elastic deformation a material changes shape when a stress is applied to it but goes back to its original state when the stress is removed.
- electromotive force — a source of energy that can cause a current to flow in an electrical circuit or device
- electrostatic field — an electric field associated with static electric charges
- entry qualification — the qualifications and conditions required to join an organization, club, etc
- family practitioner — medical specialization in general practice, requiring training beyond that of general practice and leading to board certification.
- fellow countrywoman — a fellow countrywoman is a female citizen of the same state as the person speaking, writing, or being referred to
- female circumcision — clitoridectomy.
- first-sale doctrine — a legal principle allowing the purchaser of a lawfully made copy of a copyright-protected work to sell or give away that copy without permission but not to reproduce it.
- flannelmouth sucker — a sucker, Catostomus latipinnis, of the Colorado River and its tributaries.
- focal plane shutter — an opaque shield in a camera, lying in the focal plane of the lens, that, when tripped, admits light to expose the film or plate for a predetermined period, usually a fraction of a second
- focal-plane shutter — a camera shutter situated directly in front of the film.
- foregone conclusion — an inevitable conclusion or result.
- four colour theorem — four colour map theorem
- four eyes principle — the requirement that a business transaction be approved by at least two individuals
- fractal compression — (algorithm) A technique for encoding images using fractals.
- fractional currency — coins or paper money of a smaller denomination than the basic monetary unit.
- fraternal insurance — insurance underwritten by a fraternal society, under either a legal reserve plan or an assessment plan.
- frederick william i — 1688–1740, king of Prussia 1713–40.
- frill-necked lizard — a large arboreal insectivorous Australian lizard, Chlamydosaurus kingi, having an erectile fold of skin around the neck: family Agamidae (agamas)
- frontier technology — innovative or new technology
- full-wave rectifier — a rectifier that transmits both halves of a cycle of alternating current as a direct current.
- functional currency — Functional currency is the main currency used by a business.
- general post office — (in the U.S. postal system) the main post office of a city, county, etc., that also has branch post offices. Abbreviation: G.P.O., GPO.
- grandfather's clock — a pendulum floor clock having a case as tall as or taller than a person; tall-case clock; long-case clock.
- great wall of china — a system of fortified walls with a roadway along the top, constructed as a defense for China against the nomads of the regions that are now Mongolia and Manchuria: completed in the 3rd century b.c., but later repeatedly modified and rebuilt. 2000 miles (3220 km) long.
- guerrilla financing — the use of unconventional and marginally legal means to capitalize enterprises
- gulf of carpentaria — a shallow inlet of the Arafura Sea, in N Australia between Arnhem Land and Cape York Peninsula
- half wave rectifier — A half wave rectifier removes the negative component of an alternating signal leaving only the positive part.
- half-wave rectifier — a rectifier that changes only one half of a cycle of alternating current into a pulsating, direct current.
- halt and catch fire — (humour, processor) (HCF) Any of several undocumented and semi-mythical machine instructions with destructive side-effects, supposedly included for test purposes on several well-known architectures going as far back as the IBM 360. The Motorola 6800 microprocessor was the first for which an HCF opcode became widely known. This instruction caused the processor to read every memory location sequentially until reset.
- helsinki conference — Conference on Security and Cooperation in Europe.
- house of councilors — the upper house of the Japanese diet.
- hyperbolic function — a function of an angle expressed as a relationship between the distances from a point on a hyperbola to the origin and to the coordinate axes, as hyperbolic sine or hyperbolic cosine: often expressed as combinations of exponential functions.
- hyperfocal distance — the distance, at a given f number, between a camera lens and the nearest point (hyperfocal point) having satisfactory definition when focused at infinity.
- imperial preference — a proposed system whereby free trade and levelled tariffs would exist between nations belonging to the British Commonwealth, in order to increase the prosperity of and unity between these nation
- incomplete fracture — a fracture extending partly across the bone.
- inferiority complex — Psychiatry. intense feeling of inferiority, producing a personality characterized either by extreme reticence or, as a result of overcompensation, by extreme aggressiveness.
- inglenook fireplace — a large fireplace with a space on either side
- interfacial tension — the surface tension at the interface of two liquids.
- interferometrically — By means of interferometry.
- italian east africa — a former Italian territory in E Africa, formed in 1936 by the merging of Eritrea and Italian Somaliland with newly conquered Ethiopia: taken by the British Imperial forces 1941.
- jacques montgolfier — Jacques Étienne [zhahk ey-tyen] /ʒɑk eɪˈtyɛn/ (Show IPA), 1745–99, and his brother Joseph Michel [zhaw-zef mee-shel] /ʒɔˈzɛf miˈʃɛl/ (Show IPA) 1740–1810, French aeronauts: inventors of the first practical balloon 1783.
- judicial conference — a conference of judges held to discuss improvements in methods or judicial procedure through court rules or otherwise.
- leading aircraftman — the rank above aircraftman
- left-luggage locker — a coin-operated locker in which luggage can be left
- letters of credence — credentials issued to a diplomat or other governmental representative for presentation to the country to which he or she is sent.