Hold on!

hold on

1. To physically grip something. Hold onto the railing so that you don't lose your balance.
2. To wait or pause. Often used as an imperative. Hey, hold on—that's not what I'm saying at all. If you'll just hold on a minute, I'll pull up your file.
3. To continue or persist despite challenges. The company will not be able to hold on if we lose money again this quarter.
See also: hold, on
Farlex Dictionary of Idioms.

Hold on (a minute)!

 and Hold on for a minute!
Stop right there!; Wait a minute! (Minute can be replaced by moment, second, or other time periods.) Bob: Hold on, Tom. Tom: What? Bob: I want to talk to you. "Hold on!" hollered Tom. "You're running off with my shopping cart!"
See also: hold
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • lose (one's) grip on (someone or something)
  • lose one’s grip
  • lose one’s hold
  • lose (one's) hold on (someone or something)
  • lose hold on
  • cough it up
  • come in
  • come in a certain position
  • come on in
  • button it!