Not idle; active or in use.

(organic chemistry) Any halogenated derivative of ethane that contains one bromine atom and two chlorine atoms, but especially 2-bromo-1,1-dichloro-ethane

plural of V.V.I.P.

(military, weaponry) a type of theoretical radiological nuclear weapon that relies on an induced rapid change in the state of nuclear isomers to generate an intense gamma ray flash.