A piece is en prise when it is attacked and undefended, so the opponent can simply capture it for free.
‘En prise’ is French for ‘in take’ — it describes any piece or pawn that the opponent can grab without giving anything back. The piece is either completely undefended, or defended by fewer pieces than are attacking it.
Leaving a piece en prise is the most common way club players lose material. It usually happens when you focus on your own plan and forget to check whether your last move left something loose, or whether the opponent’s move just created a new attacker.
The fix is a simple habit: after every move, scan for your pieces (and the opponent’s) that are attacked and not defended. Loose pieces drop off — both yours to lose and theirs to win.
It means a piece is sitting where it can be captured for free — attacked and either undefended or under-defended. The opponent can take it without losing anything in return.
After every move, do a quick scan: list every piece that is attacked, then check whether it is defended. Any attacked-and-undefended piece is hanging and needs attention before you do anything else.
BetterChess is a practice tool — we make no guarantee you'll reach 1800 or any rating. Definitions are standard chess terminology; every diagram position is checked legal with the same engine the board runs.