What does "offset" mean?

Offset: A sum, account, or value set off against another sum or account, as an equivalent; hence, anything which is given in exchange or retaliation; a set-off.

Additional senses

  1. 2.A spur from a range of hills or mountains.
  2. 3.(Arch.) A horizontal ledge on the face of a wall, formed by a diminution of its thickness, or by the weathering or upper surface of a part built out from it; -- called also set-off.
  3. 4.(Surv.) A short distance measured at right angles from a line actually run to some point in an irregular boundary, or to some object.
  4. 5.(Mech.) An abrupt bend in an object, as a rod, by which one part is turned aside out of line, but nearly parallel, with the rest; the part thus bent aside.
  5. 6.(Print.) A more or less distinct transfer of a printed page or picture to the opposite page, when the pages are pressed together before the ink is dry or when it is poor. Offset staff (Surv.), a rod, usually ten links long, used in measuring offsets.
  6. 7.To set off; to place over against; to balance; as, to offset one account or charge against another.
  7. 8.To form an offset in, as in a wall, rod, pipe, etc.
  8. 9.To make an offset.

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