τριακοντάπηχυς

υ,
A. thirty cubits long, πηδάλια Callix. 1, cf. Philostr. Her. 1.3 (but divisim τριάκοντα πηχῶν D.S. 3.36).
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
An open-access project