the.com/gaiety

Joy that forgot it was supposed to be embarrassed about itself.

means Lighthearted, merry cheerfulness — the state of bright, carefree fun.

from From French gaieté, from gai ('gay,' meaning joyful or lively), a word whose own roots are murky — possibly linked to Old High German wahi ('pretty'), though etymologists aren't fully settled. It entered English in the 1600s, carrying that bubbly French brightness with it, long before 'gay' narrowed toward its modern primary sense.

old meaning
once implied sexual promiscuity, not just cheerfulness
theater link
many Gaiety Theatres named for the feeling, not the venue
victorian decline
word lost favor as emotions got more buttoned-up
root word
from gai, old french for lighthearted or showy
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