18-letter words containing m, e, s, t, o
- wattless component — Electricity. reactive component.
- wesleyan methodist — a member of any of the churches founded on the evangelical principles of John Wesley.
- western meadowlark — any of several American songbirds of the genus Sturnella, of the family Icteridae, especially S. magna (eastern meadowlark) and S. neglecta (western meadowlark) having a brownish and black back and wings and a yellow breast, noted for their clear, tuneful song.
- what has become of — If you wonder what has become of someone or something, you wonder where they are and what has happened to them.
- white-footed mouse — any of several North American woodland mice of the genus Peromyscus, especially P. leucopus, having white feet and undersides.
- woe betide someone — misfortune will befall someone
- woman of the house — lady of the house.
- 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.
- wrangell mountains — a mountain range in SE Alaska, extending into the Yukon, Canada. Highest peak: Mount Blackburn, 5037 m (16 523 ft)
- x-ray spectrometer — a spectrometer using x-rays to activate the inner electrons of an atom in order to separate and identify the chemical constituents of a substance and their concentrations.
- x-ray spectrometry — the use of an x-ray spectrometer.
- zermelo set theory — (mathematics) A set theory with the following set of axioms: Extensionality: two sets are equal if and only if they have the same elements. Union: If U is a set, so is the union of all its elements. Pair-set: If a and b are sets, so is {a, b}. Foundation: Every set contains a set disjoint from itself. Comprehension (or Restriction): If P is a formula with one free variable and X a set then {x: x is in X and P(x)}. is a set. Infinity: There exists an infinite set. Power-set: If X is a set, so is its power set. Zermelo set theory avoids Russell's paradox by excluding sets of elements with arbitrary properties - the Comprehension axiom only allows a property to be used to select elements of an existing set.