A difference between the value of a function evaluated at a number, and the value of the same function evaluated at a different number, a fixed distance from the first.

(botany, zoology) Of a side that is facing away from the axis or central line, such as the underside of a leaf; or the back of an animal.

cue; the stick used to propel the ball in snooker, billiards, etc.

(idiomatic) Finished; concluded; able to be regarded as a matter of record.