Anneal
Meaning: to make metal or glass soft by heating and then cooling it slowly
Sentence: An annealing schedule of learning rates was used.
Synonyms: harden, temper, thicken, toughen
Antonyms: flex, liquefy, melt, soften, weaken
Anticlastic
Meaning: having opposite curvatures at a given point
Antispasmodic
Meaning: (chiefly of a drug) used to relieve spasm of involuntary muscle
Ashy
Meaning: Of a pale greyish colour; ashen.
Synonyms: bleached, blonde, golden
Antonyms: dark, brunet, brunette