poecilonymy
From ZooTerms (Dictionary of Invertebrate Zoology)
poecilonymy also pecilonymy (noun; Greek poikilo, varied; onyma, name): 1. The use of two or more terms to indicate the same thing.
2. A synonym, i.e., a systematic name, as of a species or genus, being designated and later regarded as an incorrect form, rejected and replaced with another more correctly applied.
