Synonyms for Flourish:
General:
* Thrive
* Prosper
* Succeed
* Grow
* Develop
* Advance
* Expand
* Boom
* Blossom
* Burgeon
* Flourish
* Exuberate
More Specific:
* For individuals: Excel, shine, soar, triumph, dominate
* For businesses: Boom, thrive, prosper, take off, soar, expand
* For art or writing: Thrive, blossom, soar, flourish, excel, shine, resonate
* For plants: Bloom, blossom, grow, thrive
Figurative:
* Radiate, flourish, wave, swing, dance, sway, ripple
Antonyms for Flourish:
General:
* Wither
* Decline
* Decay
* Fail
* Collapse
* Diminish
* Die out
* Perish
* Vanish
* Fade away
More Specific:
* For individuals: Fail, struggle, struggle, falter, decline
* For businesses: Fail, struggle, collapse, decline, stagnate, shrink
* For art or writing: Fail, flop, fall flat, lack impact, fall short
* For plants: Wither, die, wilt, fade, droop
Figurative:
* Fade, shrink, shrivel, stagnate, languish
Remember, the best synonym or antonym will depend on the context in which you are using the word "flourish."