Insurance ( blackjack)

If the dealer's up card is an ace (or ten as up card), he or she will call for insurance.
When you place an insurance wager, you are betting that the dealer has Blackjack.
To make an insurance wager, pace an amount, up to one half your original bet on the insurance line when the dealer calls for insurance. If the dealer has Blackjack you win your insurance bet, but lose your original bet. If the dealer does not have Blackjack, you lose your insurance bet and the game continues. Taking the insurance bet is highly advantageous to the house, unless the player is card counting.

Insurance ( poker )

In big bet poker, it is possible to reach a situation in which you are uncomfortable with the amount of money you have invested in a pot. To reduce variance, players will sometimes take insurance against an unfortunate outcome, essentially selling the actual outcome of the hand for its mathematical equity (at a slight discount).

Insurance (general terms )

A side bet that the dealer has a blackjack. It’s offered when the dealer's upcard is an ace.
If the dealer has a blackjack, the bet is paid 2-1. If the dealer does not, the insurance bet loses.