'aspidobranchiate' originates from New Latin, specifically the word 'Aspidobranchia', where 'aspido-' meant 'shield' and 'branchia' meant 'gills'.

'aspidobranchiate' changed from the New Latin word 'Aspidobranchia' (formed from Greek roots) and eventually became the modern English term 'aspidobranchiate' used in 19th-century taxonomic descriptions.

Initially, it meant 'having shield-like gills or belonging to the group Aspidobranchia', but over time it came to be used specifically for members or characteristics of that (now-obsolete) taxonomic grouping.