I must say good night

I must say good night

A phrase that precedes one's departure at nighttime. Adam's waiting for me at home, so I must say good night. Ooh, the last train comes in five minutes, so I must say good night, my friends!
See also: good, must, night, say
Farlex Dictionary of Idioms.

I must say good night.

an expression announcing the speaker's intention of leaving for the night. Jane: It's late. I must say good night. Bob: Can I see you again? Jane: Call me. Good night, Bob. Bob: Good night, Jane. Sue: I must say good night. Mary: Good night, then. See you tomorrow.
See also: good, must, night, say
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • I must be off
  • I‘ve gotta fly
  • I’ve got to fly
  • I gotta fly
  • I've got to fly
  • I'm there
  • I’m there!
  • (one) (had) better be off
  • Here’s the deal
  • here's the deal