The term caesura (alternate cesura), Greek tomḗ (‘a cut’), referring to a division within a line of verse seems to date back no earlier than the 2nd century CE. The term can refer either to a position in an abstract metrical scheme regularly associated with a word division or the specific implementation of such a division in a line of verse. In contemporary literature, the term is used most broadly to refer to any word division within a line of verse. [excerpt]
Brown, H. Paul. "Caesurae." Encyclopedia of Ancient Greek Language and Linguistics. Ed. Georgios K. Giannakis. (Brill Online, 2014).