20-letter words containing d, a, c, h
- magnetohydrodynamics — the branch of physics that deals with the motion of electrically conductive fluids, especially plasmas, in magnetic fields. Abbreviation: MHD.
- mail exchange record — (messaging) (MX Record) A DNS resource record type that says which SMTP server handles electronic mail for a particular domain. E.g. the MX record foo.co.uk. 1054 IN MX 10 mail.foo.co.uk. means that mail for an address like "[email protected]" should be sent to "mail.foo.co.uk". There can be several servers for a domain. The "10" is a priority - the server with the lowest number will be tried first.
- matched-pairs design — (of an experiment) concerned with measuring the values of the dependent variables for pairs of subjects that have been matched to eliminate individual differences and that are respectively subjected to the control and the experimental condition
- mechanical advantage — the ratio of output force to the input force applied to a mechanism.
- mechanical impedance — impedance (def 2).
- mechanical-impedance — Electricity. the total opposition to alternating current by an electric circuit, equal to the square root of the sum of the squares of the resistance and reactance of the circuit and usually expressed in ohms. Symbol: Z.
- meta-dichlorobenzene — a colorless liquid, C 6 H 4 Cl 2 , soluble in alcohol and ether: used as a fumigant and insecticide.
- nondirective therapy — client-centered therapy.
- north atlantic drift — an ocean current flowing NE toward the British Isles, formed by the convergence of the Gulf Stream and the Labrador Current SE of Newfoundland.
- north canadian river — a river in NE New Mexico, E Texas, and E Oklahoma, flowing SE to the Canadian River. 760 miles (1223 km) long.
- north richland hills — a town in N Texas.
- northern white cedar — any of several chiefly coniferous trees valued for their wood, especially Chamaecyparis thyoides, of the eastern U.S., or Thuja occidentalis (northern white cedar) of northeastern North America.
- not hold a candle to — to be inferior or contemptible in comparison with
- not worth the candle — not worth the price or trouble entailed (esp in the phrase the game's not worth the candle)
- officer of the guard — an officer, acting under the officer of the day, who is responsible for the instruction, discipline, and performance of duty of the guard in a post, camp, or station. Abbreviation: OG, O.G.
- orthopaedic mattress — a specially firm mattress designed to help correct or ameliorate the discomfort of disorders of the spine and joints
- orthophosphoric acid — a colorless, crystalline solid, H 3 PO 4 , the tribasic acid of pentavalent phosphorus: used chiefly in fertilizers, as a source of phosphorus salts, and in soft drinks as an acidulant and flavoring agent.
- para-dichlorobenzene — a white, crystalline, volatile, water-insoluble solid, C 6 H 4 Cl 2 , of the benzene series, having a penetrating odor: used chiefly as a moth repellent.
- peroxysulphuric acid — a white hygroscopic crystalline unstable oxidizing acid. Formula: H2SO5
- perpendicular gothic — the style of Gothic architecture in England during the 14th and 15th centuries, characterized by tracery having vertical lines, a four-centred arch, and fan vaulting
- phosphoric anhydride — phosphorus pentoxide.
- physical double star — two stars that appear as one if not viewed through a telescope with adequate magnification, such as two stars that are separated by a great distance but are nearly in line with each other and an observer (optical double star) or those that are relatively close together and comprise a single physical system (physical double star)
- physiologic jaundice — a transitory jaundice that affects some infants for the first few days after birth.
- potassium dichromate — an orange-red crystalline soluble solid substance that is a good oxidizing agent and is used in making chrome pigments and as a bleaching agent. Formula: K2Cr2O7
- powhatan confederacy — a network of Algonquian-speaking Indian settlements in Virginia that was ruled by Powhatan.
- poza rica de hidalgo — a city in N Veracruz, in E Mexico.
- prohibited substance — a substance, such as a drug, etc, that is banned or forbidden by law or other authority
- pseudo-psychological — of or relating to psychology.
- pseudoparenchymatous — (in certain fungi and red algae) a compact mass of tissue, made up of interwoven hyphae or filaments, that superficially resembles plant tissue.
- read the riot act to — to command to stop doing something regarded as wrong, under threat of punishment
- redheaded woodpecker — a North American woodpecker (Melanerpes erythrocephalus), with a bright-red head and neck, black back, and white underparts
- ring-necked pheasant — a gallinaceous Asian bird, Phasianus colchicus, having a white band around its neck, introduced into Great Britain, North America, and the Hawaiian Islands.
- sarcastic fringehead — any fish of the genus Neoclinus, characterized by a row of fleshy processes on the head, as N. blanchardi (sarcastic fringehead) of California coastal waters.
- scavenger's daughter — an instrument of torture that doubled over and squeezed the body so strongly and violently that blood was brought forth from the ears and nose: invented in 16th-century England.
- schizoid personality — sb with identity disorder
- schrodinger equation — the wave equation of nonrelativistic quantum mechanics. Also called Schrödinger wave equation. Compare wave equation (def 2).
- schwarzschild radius — the radius at which a gravitationally collapsing celestial body becomes a black hole.
- schwarzschild sphere — the sphere which surrounds a non-rotating uncharged black hole, from within which no information can escape because of gravitational forces
- season ticket holder — a person who has a season ticket
- second-hand bookshop — a shop selling second-hand books
- sellers screw thread — a thread form in a system of standard sizes proposed by Sellers in 1884 and later accepted as standard in the USA, having a 60° flank angle with a flat top and foot
- short back and sides — If a man has a short back and sides, his hair is cut very short at the back and sides with slightly thicker, longer hair on the top of the head.
- silicon tetrahydride — silane (def 1).
- spherical coordinate — 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.
- 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.
- stallman, richard m. — Richard Stallman
- switchboard operator — a person who operates an installation in a telephone exchange, office, hotel, etc, at which the interconnection of telephone lines is manually controlled
- synchronized skating — the art or sport of teams of up to twenty skaters holding onto each other and moving in patterns in time to music
- tetrahydrocannabinol — a compound, C 21 H 30 O 2 , that is the physiologically active component in cannabis preparations (marijuana, hashish, etc.) derived from the Indian hemp plant or produced synthetically. Abbreviation: THC.
- the grove of academe — the academic world