Lewis Short
(adjective) : grōmātĭcus (grūm-), a, um, groma
* Of or belonging to field-surveying or castrametation.
* Adj.: disciplina,Cassiod. Varr. 3, 52.
* Subst.: grōmā-tĭca (grūm-), ae, f., the art of field-surveying or castrametation, Cassiod. Varr. 3, 52.
* Grōmātĭci, ōrum, m., writers on field-surveying, Hyg. de Mun. Castr. § 12.
Charlton T. Lewis, Charles Short, A Latin Dictionary