In chess a trap is a where you attack a piece and it has no way to safety, including moving or another piece protecting it. The following illustrates a position where the white queen can trap blacks Knight : [SetUp "1"] [FEN "8/8/8/3k4/7n/8/4Q3/K7 w - - 0 1"] {[%csl Gg4,Rg6,Rf5,Rf3,Rg2] The green square is where the queen delivers the trap. The red squares show the only squares the Knight can move to. There is no piece to come to the Knights rescue } 1.Qg4 {The white Queen traps the Knight } Ng6 2.Qxg6{White captures the Knight!} 1-0 You must activate JavaScript to enhance chess game visualization.