18-letter words containing i, s, n, a
- war risk insurance — life insurance for members of the armed forces.
- wardrobe assistant — a person who assists the wardrobe mistress in a theatre
- warrant of fitness — a six-monthly certificate required for motor vehicles certifying mechanical soundness
- waste minimization — a policy of generating as little waste as possible
- water stick insect — a slender sticklike flightless water bug, Ranatra linearis, that is predatory on small creatures such as water fleas
- 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.
- weberian apparatus — (in certain fishes) a chain of small bones and ligaments connecting the inner ear with the air bladder.
- welland ship canal — a ship canal in S Canada, in Ontario, connecting Lakes Erie and Ontario: 8 locks. 25 miles (40 km) long.
- 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.
- wesleyan methodist — a member of any of the churches founded on the evangelical principles of John Wesley.
- western alienation — a feeling of resentment by some inhabitants of western Canada against perceived favouritism by the national government towards the eastern provinces
- 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.
- wild passionflower — the maypop, Passiflora incarnata.
- wildlife sanctuary — an area where wild animals and plants are protected
- wilson's phalarope — a phalarope, Phalaropus tricolor, that breeds in the prairie regions of North America and winters in Argentina and Chile.
- winged everlasting — a bushy composite plant, Ammobium alatum, of Australia, having winged branches, javelin-shaped leaves, and white flowers.
- without hesitation — immediately, willingly
- women at point sur — a narrative poem (1927) by Robinson Jeffers.
- 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.
- world championship — an international competition in a particular sport or activity for people all around the world
- wrangell mountains — a mountain range in SE Alaska, extending into the Yukon, Canada. Highest peak: Mount Blackburn, 5037 m (16 523 ft)
- writ of assistance — a writ issued by a superior colonial court authorizing officers of the British crown to summon aid and enter and search any premises.
- wrongful dismissal — the act of making someone redundant for reasons which are illegal or unjust
- yeast nucleic acid — RNA.
- young conservative — a member of the youth section of the United Kingdom Conservative Party
- yves saint laurent — Louis Stephen [lwee ste-fen] /lwi stɛˈfɛn/ (Show IPA), 1882–1973, prime minister of Canada 1948–57.
- zone of saturation — the ground below the water table