Synonyms for sweeten
verb
To make sweet
sugar, add sugar, add sweetening, make toothsome, give a sweet flavor to, mull; see also flavor.
Antonyms sour*, make sour, make bitter.
To make fresh
purify, freshen, remove salt from, fumigate, disinfect, cleanse, revive, renew, ventilate.
See sweeten in Webster's New World Roget's A-Z Thesaurus II
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