Meaning of second base in English:

second base

Pronunciation /ˌsɛk(ə)nd ˈbeɪs/

noun

  • 1Baseball
    The second of the four bases which the batter must touch in succession in order to score a run.

  • 2 slang (chiefly North American). The second of four notional stages of sexual activity, usually characterized as the act of touching the breasts.

Origin

Mid 19th century; earliest use found in By-laws & Rules Knickerbocker Base Ball Club. From second + base.