Entry 1 sense Webster, 1913 macamba · IPA 01 n. A tropical American feather palm (Acrocomia aculeata) having a swollen spiny trunk and edible nuts. 1. A tropical American feather palm (Acrocomia aculeata) having a swollen spiny trunk and edible nuts. Syn. grugru, gri gri, grugru palm, Acrocomia aculeata.