'ectasis' originates from Greek, specifically the word 'ἐκτασις' (ektasis), where 'ek-' meant 'out' and 'tasis' meant 'stretching'.

'ectasis' changed from the Ancient Greek word 'ἐκτασις' and passed into New Latin/medical Latin usage as 'ectasis' before being adopted into English medical terminology in the 19th century.

Initially it meant 'stretching out' in a general sense; over time it evolved into the modern medical meaning of 'dilation or pathological expansion of a structure'.