'avicular' originates from Latin, specifically the word 'avicularis', where 'avis' meant 'bird' and the diminutive element '-culus' (in 'aviculus') indicated 'little'.

'avicular' developed from Latin 'avicularis' (adjectival form related to 'aviculus' = 'little bird') and entered Late/Medieval Latin usage before being adopted into English in its modern adjectival form.

Initially it referred more narrowly to 'of or relating to little birds' (from the diminutive), but over time it broadened to mean 'pertaining to birds' or 'avian' in general.