Synonyms for Sex (same or very similar meaning)
WordNet sense 1 (all of the feelings resulting from the urge to gratify sexual impulses):
sexual urge
WordNet sense 2 (the properties that distinguish organisms on the basis of their reproductive roles):
gender, sexuality
WordNet sense 3 (stimulate sexually):
arouse, excite, turn on, wind up
WordNet sense 4 (activities associated with sexual intercourse):
sexual activity, sex activity, sexual practice
From the ODE community, based on WordNet
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