a tool or implement with two or more prongs set on the end of a handle, e.g.:

an attack by a chess piece, e.g. a knight, on two pieces simultaneously

to divide into two or more branches

You'll find the garage just where the road forks

to make a turn into one of the branches of a fork

We forked left at the inn

informal (+ out/up) to make a payment or contribution

to raise, pitch, dig, or work (something) with a fork

We watched them fork hay in the traditional way

to attack (two chessmen) simultaneously

informal (+ out/over/up) to pay or contribute (a specified amount)

He's forked out half of his salary for a new car