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titty

1 American  
[tit-ee] / ˈtɪt i /

noun

Slang: Usually Vulgar.

PLURAL

titties
  1. a breast or teat.


titty 2 American  
[tit-ee] / ˈtɪt i /
Or tittie

noun

Scot. Informal.

PLURAL

titties
  1. sister.


Etymology

Origin of titty1

First recorded in 1740–50; tit 2 + -y 2

Origin of titty2

1715–25; perhaps originally form of sister in children's speech