Giving-in means to surrender, yield or submit. Antonyms of giving-in would be defiance, resistance, and opposition. When someone is in a situation where they refuse to give-in, they are displaying a form of resistance. Defiance involves openly and boldly challenging authority or expectations, whereas resistance is a subtler form of opposition, often through non-cooperation. Opposition, on the other hand, is simply choosing to take a different course of action than that expected, without necessarily defying or resisting it. The antonyms of giving-in imply strength and independence, and choosing not to concede is often a powerful way to assert oneself.