simultaneity Simulium • simultaneous · · · Info · Definitions · Synonyms · Characters · · simultaneity · · Text Latin · · Script 12 · · Length Definitions · · · (noun) happening or existing or done at the same time. Synonyms: simultaneousness. · · Noun Definition 1 Synonyms · · · simultaneousness · · Synonym 1 Characters · · a latin small letter a U+0061 e latin small letter e U+0065 i latin small letter i U+0069 l latin small letter l U+006C m latin small letter m U+006D n latin small letter n U+006E s latin small letter s U+0073 t latin small letter t U+0074 u latin small letter u U+0075 y latin small letter y U+0079