Yb uncommon formal informal noun 1. a soft silvery metallic element; a rare earth of the lanthanide series; it occurs in gadolinite and monazite and xenotime Synonymsytterbiumatomic number 70 Related words Broader terms metallic element Parts gadolinitemonazitexenotime WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
