'autotomise' originates from Greek via New Latin and modern English formation: Greek 'autotomia' (αὐτοτομία) from 'auto-' meaning 'self' and 'tomia' from 'temnein' meaning 'to cut', with the English verbalizing suffix '-ise'.

'autotomy' entered English from New Latin 'autotomia' (from Greek), and the verb 'autotomise' (also spelled 'autotomize' in US English) was later formed from this noun by adding the verbal suffix (-ise/-ize).

Initially it referred generally to 'self-cutting' or 'self-incision' in the literal Greek sense; over time it has come to mean specifically the biological behaviour of intentionally shedding or dropping a part of the body (e.g. a tail) as a defensive strategy.