From WordNet (r) 2.0 (August 2003) [wn]:
grot
n : a small cave (usually with attractive features) [syn:
grotto]
From The Collaborative International Dictionary of English v.0.48 [gcide]: Grot \Grot\ (gr[o^]t), n. [F. grotte, It. grotta. See Grotto.] A grotto. [Poetic] --Milton. [1913 Webster] Grot From The Collaborative International Dictionary of English v.0.48 [gcide]: Grot \Grot\, Grote \Grote\ (gr[=o]t), n. A groat. [Obs.] --Chaucer. [1913 Webster]