The American Heritage △Guaranteed to get or have: You're in for a big surprise.Cobuild:
Webster Learners △informal. sure to experience (something): Boy, is she in for a surprise! (— see also have it in for at have)
Princeton WordNet △certain to get or have: he knew he was in for a licking.
△If you say that someone is in for a shock or a surprise, you mean that they are going to experience it: You might be in for a shock at the sheer hard work involved.cf.
△If someone has it in for you, they dislike you and try to cause problems for you.(INFORMAL): The other kids had it in for me.
OALD △be in for it (British English also be for it) (informal) to be going to get into trouble or be punished: We'd better hurry or we'll be in for it.
OALD △come in for something [no passive] to receive something, especially something unpleasant: The government's economic policies have come in for a lot of criticism.