first base

/F ER1 S T B EY1 S/
noun
  1. 1

    The base after home plate in a counter-clockwise path around a baseball infield.

  2. 2

    (by extension) Completion of the first phase of an activity.

  3. 3

    Kissing, regarded as the first phase of a sexual relationship.

  4. 4

    The betting spot located immediately to the left of the dealer, which is first to receive cards and first to act.

Source: https://en.wiktionary.org/wiki/first%20base