'ecdysis' originates from Ancient Greek, specifically the word 'ekdysis' (ἔκδυσις), where the prefix 'ek-' meant 'out' and the root 'dysis/dýō' related to 'putting off' or 'stripping off.'

'ecdysis' entered New Latin and scientific usage from Greek 'ekdysis,' and was later adopted into Modern English in technical biological contexts (19th century onward).

Initially it meant 'a stripping off' in Greek, and over time it retained that core sense, coming to refer specifically to the biological process of shedding an outer skin or cuticle.