G / grōma
noun

grōma

gen. grōmae · gender feminine · decl. 1st
A surveyor's pole; measuring-rod
A surveyor's pole or measuring-rod, acc. to Paul. ex Fest. s. v. p. 72 Müll. and Non. 63, 6.— Hence,
the centre of a camp by extension
Transf., the centre of a camp, where the measuring-rod was planted, so as to divide the camp into four quarters by streets meeting at that point, Hyg. de Limit. p. 164 Goes.