Source : Webster's Revised Unabridged Dictionary (1913)

Xenotime \Xen"o*time\, n. [Gr. ? honoring guests or strangers;
   xe`nos guest, stranger + ? honor: cf. G. xenotim.] (Min.)
   A native phosphate of yttrium occurring in yellowish-brown
   tetragonal crystals.

Source : WordNet®

xenotime
     n : a brown-to-yellow mineral that is a phosphate of yttrium in
         crystalline form