JOINT a.
y (Law), a tenure by two or more persons of estate by unity of interest, title, time, and possession, under which the survivor takes the whole. Blackstone. -- Joint tenant (Law), one who holds an estate by joint tenancy.
KEY n.
A position or condition which affords entrance, control, pr possession, etc.; as, the key of a line of defense; the key of a country; the key of a political situation. Hence, that which serves to unlock, open, discover, or solve something unknown or difficult; as, the key to a riddle; the key to a problem. Those who ar…