Adjective
1. (Especially of an insect larva or mollusc) feeding on or boring into wood. (Google Dictionary)
2. Destructive to wood (of fungi etc.) (wiktionary.org)
Word origin: From Greek ξυλοφάγος (xulophagos) “eating wood”, from ξύλον (xulon) “wood” and φαγεῖν (phagein) “to eat”, an ancient Greek name for a kind of a worm-eating bird.