Definition of lay down
The lay down is one of the most important games in poker. It's probably the most unpleasant game to play, but it's one you'll play with great frequency. Knowing when to bluff is a skill. Knowing when to call a bet is a skill. But knowing when to lay down your hand is an even greater skill. The action of folding is probably the most important action you do at the poker table. You have to know when to fold at the right frequency, without being taken advantage of. As they say, a dollar saved is a dollar earned.