What is the name of this symbol and what does it mean?
It's a 'segno' sign. Later in the tune there a marking "D.S. al 𝄌" (short for 'dal segno al coda'). At that point you jump back to the segno sign and play all the way to the coda 𝄌 sign. Then you jump to the coda (also marked with a coda sign).
This is a segno sign. Segno is sign in Italian. It is a point that you are supposed to return to when you encounter D.S. or “dal segno” later in the piece, in this case in the third line from the bottom.
You should also follow any other instructions there. In this case it is “al Coda” (the circle with the cross in the center) where you jump from one coda sign to the other. Other common instructions are “al fine” or “and continue”. It is a very common way to avoid writing out the same music twice and shortening the written length of pieces.