21-letter words containing d, e, t, r, m, i
- vladivostok agreement — a preliminary arms control accord concluded by Soviet leader Leonid Brezhnev and U.S. President Gerald Ford in Vladivostok, U.S.S.R., in December 1974.
- well-ordering theorem — the theorem of set theory that every set can be made a well-ordered set.
- xeroderma pigmentosum — a rare inherited disease characterized by sensitivity to ultraviolet light, exposure resulting in lesions and tumors of the skin and eyes.