1, 2. feeble; breakable, frangible. Frail, brittle, fragile imply a delicacy or weakness of substance or construction. Frail applies particularly to health and immaterial things: a frail constitution; frail hopes. Brittle implies a hard material that snaps or breaks to pieces easily: brittle as glass. Fragile implies that the object must be handled carefully to avoid breakage or damage: fragile bric-a-brac.