Abandonment, n.
Etymology: [Cf. F. abandonnement.]
1. The act of abandoning, or the state of being abandoned; total desertion; relinquishment. The abandonment of the independence of Europe. Burke.
2. (Mar. Law)
The relinquishment by the insured to the underwriters of what may remain of the property insured after a loss or damage by a peril insured against.
3. (Com. Law)
2 more senses
(a) The relinquishment of a right, claim, or privilege, as to mill site, etc. (b) The voluntary leaving of a person to whom one is bound by a special relation, as a wife, husband, or child; desertion.
4. Careless freedom or ease; abandon. [R.] Carlyle.
Shades of meaning
Fernald lists abandonment only as an antonym, under defense.
He lists it without comment; the entries above explain its neighbors.