Meanings of "Wait up"
1. To delay an action, or to delay so that someone or something can catch up. A little sister may always shout "Wait up!'' because she is small.
2. Parents do this, and spouses, and so forth, when someone is expected home at a certain time (a curfew). Tardiness is very bad when someone 'waits up' for you. For good or bad reasons. slang
"Wait up" в текстове на песни
I would rather be the person you'll always be in love with
I would rather be the one you wait up for and don't sleep because of
I would rather be the one you cry for...the one that comes from the depth of you
[Villager:] Buy each other presents and then hide them very nimbly
[Olaf:] Wait up for a chubby man to shimmy down your chimney
(Breaking and entering: ok on Christmas)