| Idiom | Meaning | Example |
| under way |
started, commenced
|
The concert is under way. The band is playing O Canada.
|
| under wraps |
secret, not advertised, on the QT
|
I know the name of the winner, but I have to keep it under wraps until tonight.
|
| under your thumb |
under your control, doing your wishes
|
Willie is under your thumb now. He does what you tell him to do.
|
| underdog |
the player or team that is not likely to win
|
The Sharks are underdogs this year. People say they won't win.
|
| underhanded |
not legal, not according to rules, not above board
|
Some people say the government was underhanded in dealing with the Indians.
|
| unsung hero |
great person who has not been honored or praised, behind the scenes
|
The mothers of the graduates are the unsung heroes. The mothers are Homework Supervisors!
|
| until you're blue... |
(See till you're blue in the face)
|
|
| up a storm |
(See sing up a storm)
|
|
| up against |
competing against, trying to defeat
|
"Who were you up against?" "Gaetan Boucher, the Champion."
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| up against it |
poor, not able to pay the bills, hard up
|
We were up against it that year. The crop had failed, we had lots of bills, and none of us had a job.
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