Impossible to break; able to withstand rough usage

unbreakable plates.

impossible to break especially under ordinary usage; "unbreakable plastic dinnerwear"[ant: breakable ]

adjective

breakable , delicate , fragile , weak

adjective

adamantine , armored , brass-bound , durable , everlasting , firm , incorruptible , indestructible , infrangible , invulnerable , lasting , nonbreakable , perdurable , resistant , rugged , shatterproof , solid , tight , toughened , unshakable , unyielding , adamant , immutable , imperishable , indissoluble , inviolable , inviolable (said of a promise or vow) , inviolate , irrefragable , irrefrangible