As far as I know, a string has about four meanings.

First, the strings used to make sounds on musical instruments, later generations refer to stringed instruments, just like wind instruments.

Second, what is used to shoot the target on the bow and arrow, that is, the meaning of bowstring,

The third is sine and cosine in mathematics.

Fourth, the strings in the first quarter and the last quarter, where the string means 1/4.

I hope this helps.