18-letter words containing l, i, t, e, o, r
- triangle of forces — a triangle whose sides represent the magnitudes and directions of three forces whose resultant is zero and which are therefore in equilibrium
- trickle irrigation — drip irrigation.
- tristan und isolde — a music drama (composed, 1857–59; première, 1865) by Richard Wagner.
- trobriand islander — a native or inhabitant of the Trobriand Islands of Papua New Guinea
- tufted loosestrife — a primulaceous plant Naumburgia thyrsiflora
- turbine ventilator — a ventilator, usually mounted on the roof of a building, deck of a ship, etc., having at its head a globular, vaned rotor that is rotated by the wind, conveying air through a duct to and from a chamber below.
- turn in on oneself — to withdraw or cause to withdraw from contact with others and become preoccupied with one's own problems
- ulcerative colitis — chronic ulceration in the large intestine, characterized by painful abdominal cramps and profuse diarrhea containing pus, blood, and mucus.
- ultrasonic testing — the scanning of material with an ultrasonic beam, during which reflections from faults in the material can be detected: a powerful nondestructive test method
- ultrasonic welding — the use of high-energy vibration of ultrasonic frequency to produce a weld between two components which are held in close contact
- ultraviolet filter — a filter used on a lens to absorb ultraviolet radiation that may impart an undesirable blue cast to a photograph.
- unix international — (body) (UI) A consortium including Sun, AT&T and others formed to promote an open environment based on Unix System V, including the Open Look windowing system.
- upper palaeolithic — the latest of the three periods of the Palaeolithic, beginning about 40 000 bc and ending, in Europe, about 12 000 bc: characterized by the emergence of modern man, Homo sapiens
- upper partial tone — overtone (def 1).
- uriniferous tubule — a urine-bearing tubule in a nephron of a kidney.
- victor emmanuel ii — 1820–78, king of Sardinia 1849–78; first king of Italy 1861–78.
- watson-crick model — a widely accepted model for the three-dimensional structure of DNA, featuring a double-helix configuration for the molecule's two hydrogen-bonded complementary polynucleotide strands.
- western alienation — a feeling of resentment by some inhabitants of western Canada against perceived favouritism by the national government towards the eastern provinces
- western isles pony — a breed of large pony, typically grey, with a dense waterproof coat. The only surviving variety is the Eriskay pony
- white-collar crime — any of various crimes, as embezzlement, fraud, or stealing office equipment, committed by business or professional people while working at their occupations.
- wireless telephone — Now Rare. radiotelephony.
- wireless telephony — Now Rare. radiotelephony.
- women's liberation — a movement to combat sexual discrimination and to gain full legal, economic, vocational, educational, and social rights and opportunities for women, equal to those of men.
- wrangell mountains — a mountain range in SE Alaska, extending into the Yukon, Canada. Highest peak: Mount Blackburn, 5037 m (16 523 ft)