opposite sex

noun

: the other one of two sexes or genders

Crayfish recognize members of their species and opposite sex partly through pheromones, the signal-sending chemicals also used by many insects.

—David M. Lodge et al.

—usually used with the; used especially to refer to women from the point of view of men or to men from the point of view of women

He gets nervous around people/members of the opposite sex. [=around women]

… every father feels a pang when his daughter begins to take a "healthy" interest in the opposite sex.

—Martin Amis

Examples of opposite sex in a Sentence

Recent Examples on the Web

This includes communication between parents and offspring and mature animals of opposite sexes communicating attraction, mate choice, and trail following. —Ashleigh N. Deluca, Parents, 16 Sep. 2025

Word History

First Known Use

1696, in the meaning defined above

Rhymes for opposite sex

• annex
• annexe
• apex
• aztecs
• carex
• codecs
• codex
• convex
• cusecs
• duplex
• execs
• fedex

Medical Definition

opposite sex

noun

: the other one of two sexes or genders

—usually used with the

At some point in the lives of susceptible men, testosterone in the scalp and in other locations in the body gets changed into dihydrotestosterone, a chemical that affects the hair follicles and inhibits hair growth. Though there's no evidence that bald men suffer any loss of status with the opposite sex, most men don't welcome hair loss.

—The University of California Wellness Letter