To "put all your eggs in one basket" is to risk losing everything all at one time. Example: "My father is a very careful investor; he never puts all of his eggs in one basket." If you had a certain number of "eggs", it would be safest to put those eggs in different "baskets" and not "put them all in one basket". To "put all your eggs in one basket" would be to risk losing all of your "eggs" in case you drop that one "basket". Example: "The best way to gamble is to only bet small amounts of money and never put all your eggs in one basket." Example: "We know that you want to become an actor and we support you, but we still want you to graduate from college. Don't put all your eggs in one basket."