A lapse is a temporary failure or slip, usually a small one. When you have a lapse in concentration during class, your mind wanders for a moment and you miss what the teacher just said. When someone has a lapse in judgment, they make a poor decision they normally wouldn't make.

The word suggests something brief and unintentional. If you forget to care for your pet one morning because you were rushing, that's a lapse. If you forget for a week, that's something more serious. A usually careful student might have a lapse and forget to put their name on a paper. A normally punctual friend might have a lapse and show up late to meet you.

Lapse can also mean to expire or gradually end. A magazine subscription lapses when you don't renew it. A friendship might lapse when two people stop keeping in touch, though they could always reconnect later.

The key idea is that a lapse is temporary and often correctable. Everyone experiences lapses: brief moments when concentration fails, memory falters, or good habits slip.