once more

once more

1. One more time; again. He went over the plan once more, stressing the importance of getting the details exactly right. I read the instructions once more, just in case there was anything I might have missed. You're getting very good at playing that song, Samantha. Once more, please.
2. A phrase used when something is being repeated. Once more, everyone: this paper is due on Thursday, not Friday, as you were originally told.
See also: more, once
Farlex Dictionary of Idioms.

once more

 and one more time
Please do it one more time. Mary: You sang that line beautifully, Fred. Now, once more. Fred: I'm really tired of all this rehearsing. John (finishing practicing his speech): How was that? Sue: Good! One more time, though. John: I'm getting bored with it.
See also: more, once
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

once aˈgain/once ˈmore

one more time; another time: Once again the train was late. Let me hear it just once more.
See also: again, more, once
Farlex Partner Idioms Dictionary

once more

/again
1. Another time; again: Could you repeat yourself once more?
2. As usual; in typical fashion: Once more, you've proven yourself inept at chess.
See also: more, once
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • all at once
  • at once
  • once and for all
  • stampede out of
  • stampede out of (some place)
  • once in a while
  • (every) once in a while
  • every once in a while
  • a year and a day
  • fortune knocks once at every man's door