Entry 1 sense Webster, 1913 Rooftree /ro͞of'-trēˌ/ · Roof·tree · IPA /ˈɹufˌtɹi/ 01 n. The beam in the angle of a roof; hence, the roof itself. 1. The beam in the angle of a roof; hence, the roof itself. “Now for me the woods may wither, now for me the rooftree fall.” — Tennyson.