Cannibal squeeze or suicide squeeze is a type of squeeze in bridge or whist, in which a defender is squeezed by a card played by his partner. Normally, this occurs with less-than-perfect defense, but there are also legitimate positions where the defense could not have prevailed.
Examples
West is on lead. If he cashes the high heart, a club is thrown from the dummy, and East is squeezed. Whichever card East discards, the declarer will take two tricks in that suit. Instead, West must lead a diamond to protect the partner from subsequent endplay (if he returns a club, the declarer will take the King and put East in with another club, forcing him to lead into ♦AQ).
The most common position for a legitimate suicide squeeze occurs when a side suit is "tangled" (neither side can lead it without giving up a trick), and another suit is protected by the partner of the player on lead, as in the following diagram:
West is to lead; if he leads a diamond, it will "untangle" the suit for the declarer. However, when he leads the high heart, he induces a simple squeeze on his partner, who must either discard the high ♣7 or unguard the diamond king. (Dummy has an idle card, and East is to play before the declarer).