The Collaborative International Dictionary of English v.0.48:
Houri \Hou"ri\, n.; pl. Houris. [Per. h[=u]r[imac], h[=u]r[=a], h[=u]r; akin to Ar. h[=u]r, pl. of ahwar beautiful-eyed, black-eyed.] A nymph of paradise; -- so called by the Mohammedans. [1913 Webster]