'erotema' originates from Greek, specifically the word 'erōtēma' (Ἐρώτημα), where 'erōta-' related to asking or questioning.

'erotema' passed from Greek 'erōtēma' into learned use in Medieval and Modern Latin and then into English as a technical rhetorical term.

Initially it simply meant 'a question' in Greek, but in English its use has become specialized to mean 'a rhetorical question' (a question posed for effect rather than information).