Lewis Short
(adjective) : hărēnārĭus (aren-), a, um, harena.
* Prop., of or pertaining to sand: lapis, sandstone (= lapis bibulus of Verg.), Serv. Verg. G. 2, 348.
* Transf., of or pertaining to the amphitheatre: fera,destined for the arena,Arn. 29, 1.
* Hence, subst.
* Hărēnārĭus, i, m.
* A combatant in the amphitheatre, a gladiator, Dig. 22, 5, 21; 36, 1, 5; Cod. Just. 3, 27, 11; Petr. 126, 6; Inscr. Orell. 4063 (but cf. Orell. ad loc.).
* Hărēnā-rĭa, ae (sc. fodina; cf.: aeraria, argentaria, etc.), f., a sand-pit, Varr. R. R. 1, 2, 23: in arenarias quasdam extra portam Esquilinam perductus occiditur,Cic. Clu. 13, 37 B. and K.
* Hărēnārĭum, ii, n., a sand-pit, Vitr. 2, 4, 2; 6, 11.
Charlton T. Lewis, Charles Short, A Latin Dictionary