7. (Mach.) A joint or other connection uniting parts of machinery, or the like, as the elastic pipe of a tender connecting it with the feed pipe of a locomotive engine; especially, a pipe fitting for connecting pipes, or pipes and fittings, in such a way as to facilitate disconnection.

8. (Brewing) A cask suspended on trunnions, in which fermentation is carried on.

Hypostatic union (Theol.) See under Hypostatic.

Latin union. See under Latin.

Legislative Union (Eng. Hist.), the union of Great Britain and Ireland, which took place Jan. 1, 1801.

Union, or Act of Union (Eng. Hist.), the act by which Scotland was united to England, or by which the two kingdoms were incorporated into one, in 1707.

Union by the first, or second, intention. (Surg.) See To heal by the first, or second, intention, under Intention.

Union down (Naut.), a signal of distress at sea made by reversing the flag, or turning its union downward.

Union jack. (Naut.) See Jack, n., 10.

Union joint. (Mech.)
   (a) A joint formed by means of a union.
   (b) A piece of pipe made in the form of the letter T.

Syn: Unity; junction; connection; concord; alliance; coalition; combination; confederacy.

Usage: Union, Unity. Union is the act of bringing two or more things together so as to make but one, or the state of being united into one. Unity is a state of simple oneness, either of essence, as the unity of God, or of action, feeling, etc., as unity of design, of affection, etc. Thus, we may speak of effecting a union of interests which shall result in a unity of labor and interest in securing a given object.

One kingdom, joy, and union without end. --Milton.

[Man] is to . . . beget Like of his like, his image multiplied. In unity defective; which requires Collateral love, and dearest amity. --Milton.

Source: Webster's Revised Unabridged Dictionary (1913)