Back (&unr_;), n. [F. bac: cf. Arm. bag, bak a bark, D. bak tray, bowl.] 1. A large shallow vat; a cistern, tub, or trough, used by brewers, distillers, dyers, picklers, gluemakers, and others, for mixing or cooling wort, holding water, hot glue, etc.
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Hop back, Jack back, the cistern which receives the infusion of malt and hops from the copper. -- Wash back, a vat in which distillers ferment the wort to form wash. -- Water back, a cistern to hold a supply of water; esp. a small cistern at the back of a stove, or a group of pipes set in the fire box of a stove or furnace, through which water circulates and is heated.
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2. A ferryboat. See Bac, 1.
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Back, a. 1. Being at the back or in the rear; distant; remote; as, the back door; back settlements.
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2. Being in arrear; overdue; as, back rent.
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3. Moving or operating backward; as, back action.
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Back blocks, Australian pastoral country which is remote from the seacoast or from a river. [Webster 1913 Suppl.] -- Back charges, charges brought forward after an account has been made up. -- Back filling (Arch.), the mass of materials used in filling up the space between two walls, or between the inner and outer faces of a wall, or upon the haunches of an arch or vault. -- Back pressure. (Steam Engine) See under Pressure. -- Back rest, a guide attached to the slide rest of a lathe, and placed in contact with the work, to steady it in turning. -- Back slang, a kind of slang in which every word is written or pronounced backwards; as, nam for man. -- Back stairs, stairs in the back part of a house; private stairs. Also used adjectively. See Back stairs, Backstairs, and Backstair, in the Vocabulary. -- Back step (Mil.), the retrograde movement of a man or body of men, without changing front. -- Back stream, a current running against the main current of a stream; an eddy. -- To take the back track, to retrace one's steps; to retreat. [Colloq.]
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Back, v. i. 1. To move or go backward; as, the horse refuses to back.
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2. (Naut.) To change from one quarter to another by a course opposite to that of the sun; -- used of the wind.
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3. (Sporting) To stand still behind another dog which has pointed; -- said of a dog. [Eng.]
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To back and fill, to manage the sails of a ship so that the wind strikes them alternately in front and behind, in order to keep the ship in the middle of a river or channel while the current or tide carries the vessel against the wind. Hence: (Fig.) To take opposite positions alternately; to assert and deny. [Colloq.] -- To back out, To back down, to retreat or withdraw from a promise, engagement, or contest; to recede. [Colloq.]
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Cleon at first . . . was willing to go; but, finding that he [Nicias] was in earnest, he tried to back out. Jowett (Thucyd. )
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