"Wait up" is a phrasal verb predominantly used in informal speech, commonly found in spoken English rather than formal writing. It is often employed in everyday conversations, particularly in two main contexts: firstly, as a request for someone to slow down or stop so that one can catch up, typically when walking or moving, e.g., "Hey, wait up! I'm coming with you!" Secondly, it is used to ask someone to remain awake and not go to bed until another person arrives, as in "I'll wait up for you until you get home." The phrasal verb is casual and friendly, often conveying a sense of urgency or a desire for consideration from the person it is directed to. Moreover, its usage often indicates a close relationship or familiarity between the speakers.
A2
Beginner
1. To stay awake or delay going to bed until someone arrives.
I’ll wait up for you until you get home from the party.
She waited up until her daughter returned from the movie.
2. To pause or stop in order to allow someone to catch up with you.
Can you wait up for me? My legs are getting tired from running.
He shouted at his friends to wait up as he struggled to keep pace on his bike.