What does the expression “to be in a hole” come from and What does in a hole mean?

The expression “to be in a hole” means: To be in debt; hence, in difficulty or trouble; in a predicament; on the spot; with one’s back to the wall.

The “hole” here is not the same one as that, in a poker game, in which one may have an ace in the hole, though this too is said to have had its origin at the poker table.

That is, so says John P. Quinn in Fools of Fortune (1892), the proprietors of a gambling joint take a certain percentage out of the pot on each hand called as the amount due the house; “a pair of aces and another pair, and you must ‘go to the hole’ with a check.

The ‘hole’ is a slot cut in the middle of the poker table, leading to a locked drawer underneath, and all checks deposited therein are the property of the keeper of the place.”