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.

[The mountains] their broad bare backs upheave
Into the clouds.
Milton.

Methought Love pitying me, when he saw this,
Gave me your hands, the backs and palms to kiss.
Donne.

This project
Should have a back or second, that might hold,
If this should blast in proof.
Shak.

A bak to walken inne by daylight.
Chaucer.

Behind one's back, when one is absent; without one's knowledge; as, to ridicule a person behind his back. -- Full back, Half back, Quarter back (Football), players stationed behind those in the front line. -- To be or lie on one's back, to be helpless. -- To put, or get, one's back up, to assume an attitude of obstinate resistance (from the action of a cat when attacked). [Colloq.] -- To see the back of, to get rid of. -- To turn the back, to go away; to flee. -- To turn the back on one, to forsake or neglect him.

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.]

I will back him [a horse] straight.
Shak.

Great Jupiter, upon his eagle backed,
Appeared to me.
Shak.

A garden . . . with a vineyard backed.
Shak.

The chalk cliffs which back the beach.
Huxley.

Have still found it necessary to back and fortify their laws with rewards and punishments.
South.

The mate backed the captain manfully.
Blackw. Mag.

To back an anchor (Naut.), to lay down a small anchor ahead of a large one, the cable of the small one being fastened to the crown of the large one. -- To back the field, in horse racing, to bet against a particular horse or horses, that some one of all the other horses, collectively designated "the field", will win. -- To back the oars, to row backward with the oars. -- To back a rope, to put on a preventer. -- To back the sails, to arrange them so as to cause the ship to move astern. -- To back up, to support; to sustain; as, to back up one's friends. -- To back a warrant (Law), is for a justice of the peace, in the county where the warrant is to be executed, to sign or indorse a warrant, issued in another county, to apprehend an offender. -- To back water (Naut.), to reverse the action of the oars, paddles, or propeller, so as to force the boat or ship backward.

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.]

Cleon at first . . . was willing to go; but, finding that he [Nicias] was in earnest, he tried to back out.
Jowett (Thucyd. )

The angel of the Lord . . . came, and rolled back the stone from the door.
Matt. xxviii. 2.

The Lord hath kept thee back from honor.
Numb. xxiv. 11.

What have I to give you back?
Shak.

Back and forth, backwards and forwards; to and fro. -- To go back on, to turn back from; to abandon; to betray; as, to go back on a friend; to go back on one's professions. [Colloq.]