Wiktionary
vb. (context idiomatic English) To eagerly anticipate; to find it unbearable to wait for a forthcoming pleasurable event
Wikipedia
"Can't Wait" is the second single released from Redman's second album, Dare Iz a Darkside. It is produced by Erick Sermon and Redman, and contains samples from "All Night Long" by Mary Jane Girls, "Caribbean Nights" by Bob James and "Just Rhymin' With Biz" by Big Daddy Kane and Biz Markie.
The song reached number five on Hot Dance Music/Maxi-Singles Sales charts, number eleven on the Hot Rap Singles chart, number sixty one on the Hot R&B/Hip-Hop Singles & Tracks chart and number ninety-four on the Billboard Hot 100 chart. It is the first of four Redman songs to reach the Billboard Hot 100 chart.
In a March 2012 interview with Complex, Erick Sermon mentioned producer Mike City used the production of Redman's "Can't Wait" as the inspiration behind two of his hits- " I Wish" by Carl Thomas as well as " Full Moon" by singer/actress Brandy.
Usage examples of "can't wait".
We're ready to hold down their subs, but I have a couple of things that just can't wait.