back

(intransitive) To go in the reverse direction.

(transitive) To support.

(nautical, of the wind) To change direction contrary to the normal pattern; that is, to shift anticlockwise in the northern hemisphere, or clockwise in the southern hemisphere.

(nautical, of a square sail) To brace the yards so that the wind presses on the front of the sail, to slow the ship.

(nautical, of an anchor) To lay out a second, smaller anchor to provide additional holding power.

(UK, of a hunting dog) To stand still behind another dog which has pointed.

(transitive) To push or force backwards.

(transitive, obsolete) To get upon the back of; to mount.

(transitive, obsolete) To place or seat upon the back.

To make a back for; to furnish with a back.

To adjoin behind; to be at the back of.

To write upon the back of, possibly as an endorsement.

(law, of a justice of the peace) To sign or endorse (a warrant, issued in another county, to apprehend an offender).

To row backward with (oars).

(MLE, transitive) To draw from behind the back [+accusative = a knife etc.] (as also back out).

(Nigeria, transitive) To carry an infant on one's back.