15-Letter Words Containing: X,O,R,S

• a crystalline amino acid obtained from gelatin or collagen

• Any member of the Paramyxoviridae family of negative-sense single-stranded RNA viruses responsible for a number of human and animal diseases.

• The fused head and thorax of spiders and crustaceans

• extinct primitive toothed bird of the Jurassic period having a long feathered tail and hollow bones; usually considered the most primitive of all birds

• greater than normal extension