a colourless nonflammable gas easily liquefied by pressure: used as a propellant in aerosols and fire extinguishers and as a refrigerant. Formula: CCl2F2
a colorless, slightly water-soluble, nonflammable gas, CCl2F2, that boils at −29°C: used chiefly as a propellant in aerosols and as a refrigerant
Word origin
[1955–60; di-1 + chloro-2 + di-1 + fluoro-1 + methane]This word is first recorded in the period 1955–60. Other words that entered Englishat around the same time include: backgrounder, new wave, rite of passage, rollout, softwaredi- is a prefix occurring in loanwords from Greek, where it meant “two,” “twice,” “double”(diphthong). On this model, di- is freely used in the formation of compound words (dicotyledon; dipolar) and in chemical terms (diatomic; disulfide)