The F clef, the clef that locates F3 (below middle C on the fourth  line).

symbol placed on the five-line staff in traditional notation indicating the pitch of the notes and locating F on the fourth line from the bottom.

 The clef in the upper staff that shows pitches mostly below middle C

A symbol placed on the fourth line of a staff to indicate that the fourth line of the staff corresponds to the F next below middle C; F clef.

The bass clef is a reversed C-shaped symbol which stand for notes played with the left hand with a resulting lower pitch.  The two dots next to the bass clef always surround and define the F Line Note [..]

a symbol placed at the beginning of the staff indicating the specific names of the lines and spaces for the staff on which it is placed. The bass clef is also called the “F clef” since it indicates th [..]

An F-clef placed at the beginning of the staff to indicate that the pitch F3 passes between the two dots of the clef, on the second staff line from the top: