acetylene acetylenation • acetylene acid · · · Info · Definitions · Synonyms · Characters · · acetylene · · Text Latin · · Script 9 · · Length 4 · · Syllables Definitions · · · (noun) a colorless flammable gas used chiefly in welding and in organic synthesis. Synonyms: ethyne, alkyne. · · Noun Definition 1 Synonyms · · · ethyne · · Synonym 1 alkyne · · Synonym 2 Characters · · a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 l latin small letter l U+006C n latin small letter n U+006E t latin small letter t U+0074 y latin small letter y U+0079