LSJ e(ca/metros

ἑξάμετρος [α^], ον,
A. of six metres, ἐν ἑ. τόνῳ in hexameter measure, Hdt.1.47; “ἐν ἔπεσι ἑ.” Id.7.220, cf. Pl.Lg.810d; ἑξάμετρα (sc. ἔπη) Arist.Rh.1404a34, Po.1449a27, Demetr.Eloc.1, etc.

Henry George Liddell. Robert Scott. A Greek-English Lexicon. revised and augmented throughout by. Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie. Oxford. Clarendon Press. 1940.

http://www.perseus.tufts.edu/hopper/text?doc=Perseus:text:1999.04.0057:entry=e(ca/metros