Abatement /(-ment)/

A·bate·ment

Abatement

n.
  1. The act of abating, or the state of being abated; a lessening, diminution, or reduction; removal or putting an end to; as, the abatement of a nuisance is the suppression thereof.
  2. The amount abated; that which is taken away by way of reduction; deduction; decrease; a rebate or discount allowed.
  3. A mark of dishonor on an escutcheon. (Her.)
  4. The entry of a stranger, without right, into a freehold after the death of the last possessor, before the heir or devisee. (Law)

Phrases & Compounds
Defense in abatement
plea to the effect that from some formal defect (e.g. misnomer, lack of jurisdiction) the proceedings should be abated.