R / rhombŏīdes
noun greek

rhombŏīdes

gen. rhombŏīdis · gender neuter · decl. 3rd
= ῥομβοειδές, in mathematics
a four-sided figure; whose opposite sides and angles are equal; a rhomboid
a four-sided figure, whose opposite sides and angles are equal, a rhomboid, Front. Expos. Form. p. 36 Goes.; Mart. Cap. 6, § 712.