heterosis Heterosiphonales • Heterosomata · · · Info · Definitions · Synonyms · Characters · · heterosis · · Text Latin · · Script 9 · · Length Definitions · · · (noun) (genetics) the tendency of a crossbred organism to have qualities superior to those of either parent. Synonyms: hybrid vigor. · · Noun Definition 1 Synonyms · · · hybrid vigor · · Synonym 1 Characters · · e latin small letter e U+0065 h latin small letter h U+0068 i latin small letter i U+0069 o latin small letter o U+006F r latin small letter r U+0072 s latin small letter s U+0073 t latin small letter t U+0074