The term 'THROWS IN' can be solved in a crossword puzzle with the answers 'ADDS' (4 letters) and 'ADZ' (3 letters). 'Throws in' is an idiom that means to add something extra or unexpected. It is often used in the context of making a contribution to a group effort, such as throwing in an extra hour of work or donating an extra item. It can also be used to describe someone who unexpectedly joins a conversation or activity.