Under the gun
The position of the player who acts first on a betting round. For instance, if
you are one to the left of the big blind, you are under the gun before the flop.
Up card
A card that is dealt to the player face up, so that all players see it. Upcards
are used inn Stud games.
Under Raise
To raise less than the previous bet; allowed only if a player is going all-in.
Underdog
A person or hand who is not mathematically favored to win a pot. For instance,
if you flop four cards to your flush, you are not quite a 2:1 underdog to make
your flush by the river(that is, you will make your flush about one in three
times).
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