Another examples are:

The word “bread” can be used to represent food in general or money (e.g. he is the breadwinner; music is my bread and butter).

The word “sails” is often used to refer to a whole ship.

The phrase "hired hands" can be used to refer to workmen.

The word "head" refers to cattle.

The word "wheels" refers to a vehicle.

References:

http://examples.yourdictionary.com/examples-of-synecdoche.html

http://theyuniversity.tumblr.com/post/109626548932/whats-up-with-metonymy-and-synecdoche