Definition of "sex"

noun:
- Either of two main divisions (either female or male) into which many organisms can be placed, according to reproductive function or organs.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License
- The distinguishing property, quality, or assemblage of properties by which organisms are classified as female or male on the basis of their reproductive organs and functions; the set of properties by which male is distinguished from female.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License
- Sexual intercourse; the act of sexual intercourse.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License
- Genitalia; a penis or vagina.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License
verb:
- To determine the biological sex of an animal.
  
  from Wiktionary, Creative Commons Attribution/Share-Alike License