Ant. Conserve, perpetuate, preserve, arrest, solidify, retain.
Alteration. Change, variation, modification, shifting, mutation.
Ant. Changelessness, identity, fixity, permanence.
Altercation. Dispute, contention, controversy, difference, quarrel, wrangle, dissension.
Ant. Concord, agreement, compromise, reconciliation, unanimity, harmony, consonance.
Alternate. Reciprocal, every other one, one after another, in turn, interchangeable, mutual.
Ant. Continuous, successive, consequent, proximate, sequent.
Alternative. Choice, option, preference, election, pick, resource.
Ant. Compulsion, quandary, necessity; fixity, changelessness.
Although. Albeit, even if, supposing, grant that.