Synonyms of the word 
LESSENED → DIMINISHED - IMPAIRED - MITIGATED - VITIATED - WEAKENED
lessened
- v. simple past tense and past participle of lessen.
- adj. Having been lessened.
diminished
- v. simple past tense and past participle of diminish.
- adj. lessened, reduced.
- adj. (music) reduced by a semitone.
impaired
- adj. Rendered less effective.
- adj. inebriated, drunk.
- v. simple past tense and past participle of impair.
- n. A criminal charge for driving a vehicle while impaired.
mitigated
- adj. lessened, reduced, diminished.
- v. simple past tense and past participle of mitigate.
vitiated
- v. simple past tense and past participle of vitiate.
weakened
- adj. Reduced, made less strong.
- v. simple past tense and past participle of weaken.
If you are interested in words, visit the following sites :
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- 1word.ws/lessened to play with words, suffixs, prefixs, etc.