2. Being in arrear; overdue; as, back rent.

3. Moving or operating backward; as, back action. 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.]

BACK
Back, v. i. [imp. & p. p. Backed (; p. pr. & vb. n. Backing.]

1. To get upon the back of; to mount. I will back him

2. To place or seat upon the back. [R.] Great Jupiter, upon his eagle backed, Appeared to me. Shak.

3. To drive or force backward; to cause to retreat or recede; as, to back oxen.

4. To make a back for; to furnish with a back; as, to back books.

5. To adjoin behind; to be at the back of. A garden . . . with a vineyard backed. Shak. The chalk cliffs which back the beach. Huxley.

6. To write upon the back of; as, to back a letter; to indorse; as, to back a note or legal document.

7. To support; to maintain; to second or strengthen by aid or influence; as, to back a friend. "Parliament would be backed by the people." Macaulay. Have still found it necessary to back and fortify their laws with rewards and punishments. South. The mate backed the captain manfully. Blackw. Mag.