18-letter words containing h, a, r, e, n
- thermal efficiency — the ratio of the work output of a heat engine to the heat input expressed in the same units of energy.
- thermogalvanometer — a thermoammeter for measuring small currents, consisting of a thermocouple connected to a direct-current galvanometer.
- thermonuclear bomb — hydrogen bomb.
- thioarsenious acid — any of a group of hypothetical acids, H3AsS3, HAsS2, and H4As2S5, known only in the forms of their salts
- third man argument — (in the philosophy of Aristotle) the argument against the existence of Platonic Forms that since the Form of Man is itself a perfect man, a further form (the "third" man) would be required to explain this, and so ad infinitum
- thorfinn karlsefni — 980–after 1007, Icelandic navigator, explorer, and leader of early colonizing expedition to Vinland, in North America.
- threatened species — a species likely, in the near future, to become an endangered species within all or much of its range.
- three-cornered hat — a triangular shaped hat which was popular in the 17th and 18th centuries; its turned up brim formed a gutter for catching rain
- three-day eventing — participation in a three day equestrian competition consisting of dressage, cross-country jumping, and stadium jumping
- to be on the radar — to be noticed or important
- to learn the ropes — If you are learning the ropes, you are learning how a particular task or job is done.
- to open your heart — If you open your heart or pour out your heart to someone, you tell them your most private thoughts and feelings.
- to the manner born — a way of doing, being done, or happening; mode of action, occurrence, etc.: I don't like the manner in which he complained.
- transit theodolite — a theodolite having a telescope that can be transited.
- triarylmethane dye — any of the class of dyes containing three aryl groups attached to a central carbon atom: used chiefly for dyeing cotton, wool, and silk.
- turn one's hand to — the terminal, prehensile part of the upper limb in humans and other primates, consisting of the wrist, metacarpal area, fingers, and thumb.
- under one's breath — the air inhaled and exhaled in respiration.
- under the aegis of — guided or protected by
- under the jackboot — If a country or group of people is under the jackboot, they are suffering because the government is cruel and undemocratic.
- urban homesteading — homesteading (def 2).
- vulcan nerve pinch — (jargon) (Or "three-finger salute", Vulcan death grip; from the old "Star Trek" TV series via Commodore Amiga hackers) The keyboard combination that forces a soft boot or jump to ROM monitor (on machines that support such a feature). On an Amiga this is done with Ctrl/Right Amiga/Left Amiga; on IBM PCs and many microcomputers it is Ctrl/Alt/Del; on Suns, L1-A; on some Macintoshes, it is
- ! Silicon Graphics users are obviously the most dextrous however, as these machines use the five-finger combination: Left Shift/Left Ctrl/Left Alt/Keypad Divide/F12. Compare quadruple bucky. - water of hydration — the portion of a hydrate that is represented as, or can be expelled as, water: now usually regarded as being in true molecular combination with the other atoms of the compound, and not existing in the compound as water.
- water on the brain — hydrocephalus.
- wernicke's aphasia — a type of aphasia caused by a lesion in Wernicke's area of the brain and characterized by grammatical but more or less meaningless speech and an apparent inability to comprehend speech.
- west-northwestward — moving, bearing, facing, or situated toward the west-northwest.
- westinghouse brake — a railroad air brake operated by compressed air.
- wheelchair housing — housing designed or adapted for a chairbound person
- whispering gallery — a space or gallery beneath a dome or broad arch in which low sounds produced at any of certain points are clearly audible at certain other distant points.
- white man's burden — the alleged duty of white colonizers to care for nonwhite indigenous subjects in their colonial possessions.
- white-faced hornet — any large, stinging paper wasp of the family Vespidae, as Vespa crabro (giant hornet) introduced into the U.S. from Europe, or Vespula maculata (bald-faced hornet or white-faced hornet) of North America.
- whitewater rafting — the sport of rafting down fast-flowing rivers, esp over rapids
- wilson's phalarope — a phalarope, Phalaropus tricolor, that breeds in the prairie regions of North America and winters in Argentina and Chile.
- woman of the world — a woman experienced and sophisticated in the ways and manners of the world, especially the world of society.
- writ of attachment — a document by which a court orders the seizing of property in order to ensure satisfaction of a judgement
- xenon hexafluoride — a colorless, crystalline compound, XeF 6 , that melts at 50°C to a yellow liquid, and boils at 75°C.