nonvolatile

from WordNet (r) 3.0 (2006)

nonvolatile
    adj 1: not volatilizing readily; "a nonvolatile acid" [syn:
           {nonvolatile}, {nonvolatilizable}, {nonvolatilisable}]
           [ant: {volatile}]

from The Collaborative International Dictionary of English v.0.48

nonvolatile \nonvolatile\ adj.
   not readily evaporated. Opposite of {volatile}.
   [WordNet 1.5]

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