selector

/S AH0 L EH1 K T ER0/
noun
  1. 1

    Someone or something which selects or chooses.

  2. 2

    An administrator responsible for selecting which players will play for a side.

  3. 3

    A matching expression in a stylesheet determining which elements in the markup are affected by a style.

  4. 4

    A pointer to a structure describing a segment of memory.

  5. 5

    A text string transmitted to a Gopher server, identifying the resource to be retrieved.

  6. 6

    A disc jockey.

Source: https://en.wiktionary.org/wiki/selector