Synonyms for Vapourific (same or very similar meaning)
WordNet sense 1 ((used of substances) capable of being volatilized):
evaporable, vaporific, vaporizable, volatilisable, volatilizable, vapourisable
WordNet sense 2 (evaporating readily at normal temperatures and pressures):
volatile
WordNet sense 3 (resembling or characteristic of vapor):
vaporous, vaporish, vapourish, vapourous
WordNet sense 4 (existing as or having characteristics of a gas):
gaseous
From the ODE community, based on WordNet
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