1. Of or belonging to the class Crustacea
   - crustacean 
2. Being or having or resembling a hard crust or shell

See also: crust, Crustacea

• X-ray machine
• X-ray photograph
• X-ray photography
• X-ray picture
• X-ray therapy
• X-ray tube
• X-raying
• X-SCID
• Xanadu
• Xanax
• xanthate
• xanthelasma
• xanthemia
• xanthene
• xanthic acid
• xanthine
• Xanthium
• xanthoma
• xanthoma disseminatum
• xanthoma multiplex
• xanthomatosis
• xanthomonad
• Xanthomonas
• Xanthophyceae
• xanthophyl