See nuclear in Webster's New World College Dictionary
adjective
of, like or forming a nucleus
of or relating to atomic nuclei: nuclear energy
of, characterized by, or operated by the use of nuclear energy: nuclear weapons
of, having, or involving nuclear weapons: nuclear warfare
See nuclear in American Heritage Dictionary 4
(no͞oˈklē-ər, nyo͞oˈ-)
adjective
Biology Of, relating to, or forming a nucleus: a nuclear membrane.
Physics Of or relating to atomic nuclei: a nuclear chain reaction.
Using or derived from the energy of atomic nuclei: nuclear power.
Of, using, or possessing atomic or hydrogen bombs: nuclear war; nuclear nations.
Usage Note: The pronunciation (no͞oˈkyə-lər), which is generally considered incorrect, is an example of how a familiar phonological pattern can influence an unfamiliar one. The usual pronunciation of the final two syllables of this word is (-klē-ər), but this sequence of sounds is rare in English. Much more common is the similar sequence (-kyə-lər), which occurs in words like particular, circular, spectacular, and in many scientific words like molecular, ocular, and vascular.