Synonyms of the word 
UNSEXY → SEXLESS - UNDERSEXED
unsexy
- adj. Not sexy.
- adj. (of research etc) Perceived as not having wide contemporary interest; plodding.
sexless
- adj. Without sexual activity.
- adj. Without physical or behavioral sexual distinction.
undersexed
- adj. Lacking sufficient sexual desire or activity; sexually unfulfilled; sexually frustrated.
If you are interested in words, visit the following sites :
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- 1word.ws/unsexy to play with words, suffixs, prefixs, etc.