19-letter words containing a, n, p
- waterglass painting — stereochromy.
- welsh mountain pony — a small sturdy but graceful breed of pony used mostly for riding, originally from Wales
- what's your poison? — what would you like to drink?
- whispering campaign — the organized spreading of insinuations or rumors to destroy the reputation of a person, organization, etc.
- whorfian hypothesis — Sapir-Whorf hypothesis.
- wraparound mortgage — a mortgage, as a second mortgage, that includes payments on a previous mortgage that continues in effect.
- xenotransplantation — xenograft.
- zenithal projection — a type of map projection in which part of the earth's surface is projected onto a plane tangential to it, either at one of the poles (polar zenithal), at the equator (equatorial zenithal), or between (oblique zenithal)
- zero and add packed — (language) (ZAP) An IBM 360/370 assembly language instruction used when performing packed arithmatic to initialise an accumulator.