Synonyms of the word 
EMBITTER → ACERBATE - ENVENOM
embitter
- v. To cause to be bitter.
acerbate
- adj. (rare) Embittered; having a sour disposition or nature.
- v. (transitive) To exasperate; to irritate.
- v. (transitive) To make bitter or sour.
envenom
- v. To poison, to put or inject venom onto or into.
- v. To acerbate.
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