'elytrous' originates from New Latin, specifically the word 'elytron', where Greek 'elytron' meant 'sheath' and the English suffix '-ous' (from Latin '-ōsus') meant 'full of, having'.

'elytrous' developed by combining Neo-Latin 'elytron' (from Greek ἔλυτρον 'elytron') with the English adjective-forming suffix '-ous'; the term entered English as a specialized entomological adjective referring to insects with elytra.

Initially the root meant 'sheath' in Greek, but over time the formed adjective came to mean 'having or relating to elytra (the hardened wing covers of certain insects)'.