From Middle English merle, from Old French merle (French merle), from Latin merula (“blackbird”) (whence the directly borrowed Middle English merule, and compare the taxonomic name Turdus merula), from Proto-Indo-European *h₂mes- (“black, blackbird”). Compare Breton moualch (“ouzel”), Welsh mwyalch (“blackbird, thrush”). Distantly related to the synonymous ouzel.