American Englishused to tell someone to stop, so that you can talk to them or go with them:
'Wait up!' he called.
WORD CHOICE: WORD CHOICE: wait, expect, look forward to, awaitWaitmeans to stay somewhere or not do something until something comes, happens etc• I'm waiting to hear from Dan before I arrange my trip.Expectmeans to believe that something will come, happen etc• The police are expecting (NOT waiting) trouble.Look forward tomeans to be excited and pleased about something that is going to happen• I'm looking forward to getting his letter.!! Wait is never followed directly by a noun. You must say wait for• She was waiting for a bus (NOT waiting a bus).In formal English, you can use await, which is followed directly by a noun• We are awaiting your instructions.
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.