18-letter words containing h, i, s, t
- phase-shift keying — (communications) (PSK) A digital modulation scheme that conveys data by changing the phase of a carrier wave. The data can either determine the absolute phase relative to the unmodulated carrier or reference signal ("coherent phase-shift keying", CPSK) or the change in phase ("differential phase-shift keying", DPSK). The number of different phases used determines the amount of data that can be transmitted in each cycle. Each cycle can be considered to constitute one "symbol", e.g. with two possible phases, each cycle carries one bit. The more phases that are used, the less tollerant to noise the transmissions becomes. Alternatives to PSK are amplitude-shift keying (ASK) and frequency-shift keying (FSK).
- phosphatidylserine — any of a class of phospholipids occurring in biological membranes and fats
- photochemical smog — air pollution containing ozone and other reactive chemical compounds formed by the action of sunlight on nitrogen oxides and hydrocarbons, especially those in automobile exhaust.
- photodecomposition — the breaking down of molecules by radiant energy.
- photoisomerization — isomerization induced by light.
- photomorphogenesis — plant development that is controlled by light.
- photosensitization — to make (a material) photosensitive, as by the application of a photosensitive emulsion.
- physical chemistry — the branch of chemistry dealing with the relations between the physical properties of substances and their chemical composition and transformations.
- physical education — systematic instruction in sports, exercises, and hygiene given as part of a school or college program.
- physical inventory — To carry out a physical inventory is to count all the stock on hand.
- physical therapist — sb who performs physiotherapy
- pick up the pieces — deal with aftermath
- pigmy hippopotamus — a related but smaller animal, Choeropsis liberiensis
- pine tree shilling — a silver coin minted in Massachusetts in the mid to late 17th century, named for the pine tree within a circle shown on the obverse side.
- pitch-and-run shot — chip shot.
- plight one's troth — to make a promise of marriage
- policeman's helmet — a Himalayan balsaminaceous plant, Impatiens glandulifera, with large purplish-pink flowers, introduced into Britain
- positively charged — having a positive charge
- potassium chlorate — a white or colorless, crystalline, water-soluble, poisonous solid, KClO 3 , used chiefly as an oxidizing agent in the manufacture of explosives, fireworks, matches, bleaches, and disinfectants.
- potassium chloride — a white or colorless, crystalline, water-soluble solid, KCl, used chiefly in the manufacture of fertilizers and mineral water, and as a source of other potassium compounds.
- potassium sulphate — a soluble substance usually obtained as colourless crystals of the decahydrate: used in making glass and as a fertilizer. Formula: K2SO4
- prime-ministership — the principal minister and head of government in parliamentary systems; chief of the cabinet or ministry: the British prime minister.
- prison authorities — the people in charge of running a prison
- processionary moth — a moth of the family Thaumetopoeidae, esp the oak processionary moth (Thaumetopoea processionea), the larvae of which leave the communal shelter nightly for food in a V-shaped procession
- proprietary rights — rights of ownership
- protease inhibitor — a drug that inhibits the action of protease, especially any of a class of antiviral drugs that prevent the cleavage and replication of HIV proteins.
- provision merchant — a person or company in the business of retailing food and other provisions
- pseudo-anarchistic — a person who advocates or believes in anarchy or anarchism.
- psychopathological — the science or study of mental disorders.
- psychotechnologist — a specialist in psychotechnology
- psychotherapeutics — psychotherapy.
- punishment beating — a form of corporal punishment carried out by a paramilitary organization on a member of another sectarian organization, usually in Northern Ireland
- puss in the corner — a parlor game for children in which one player in the middle of a room tries to occupy any of the positions along the walls that become vacant as other players dash across to exchange places at a signal.
- put one's shirt on — to bet all one has on (a horse, etc)
- pygmy hippopotamus — a small hippopotamus, Choeropsis liberiensis, of forests and swamps in western Africa.
- pyramus and thisbe — (in Greek legend) two lovers of Babylon: Pyramus, wrongly supposing Thisbe to be dead, killed himself and she, encountering him in his death throes, did the same
- quasi-metaphysical — pertaining to or of the nature of metaphysics.
- rear its ugly head — the upper part of the body in humans, joined to the trunk by the neck, containing the brain, eyes, ears, nose, and mouth.
- red-light district — an area or district in a city in which many houses of prostitution are located.
- registered charity — official aid organization
- research assistant — a graduate who is employed on a temporary or part-time basis to assist the university with academic research
- research scientist — someone who conducts scientific research or investigation, in order to discover new things, etc
- research-intensive — focusing financial and other resources on research and development as opposed to capital and labor; noting or pertaining to a high ratio of expenditure on research in relation to the value of net output.
- residential school — (in Canada) a boarding school maintained by the Canadian government for Indian and Inuit children from sparsely populated settlements
- resistance fighter — someone who fights (for freedom, etc) against an invader in an occupied country, or against their government, etc, often secretly or illegally
- rhode island white — one of a dual-purpose American breed of chickens having white feathers and a rose comb.
- right-to-work laws — a state law making it illegal to refuse employment to a person for the sole reason that he or she is not a union member.
- rotary clothesline — an apparatus of radiating spokes that support lines on which clothes are hung to dry
- rub shoulders with — to mix with socially or associate with
- rubbish collection — the collection of domestic refuse for disposal