faint
To suddenly pass out for a short time.
When you faint, you suddenly lose consciousness and fall down, usually for just a few moments. Your brain temporarily doesn't get enough blood or oxygen, so it shuts down briefly to protect itself. People might faint from standing too long in the heat, from seeing something shocking, from not eating enough, or from illness. When someone faints, they typically wake up within a minute or two, often feeling confused about what just happened.
The word also describes something so weak or slight that you can barely notice it. A faint sound is one you can hardly hear, like a whisper from across a large room. A faint smell might be barely detectable, like old perfume lingering in a closet. When you see a faint outline of something in fog or darkness, you can just barely make out its shape. If someone says they haven't the faintest idea about something, they mean they have no idea at all, not even a tiny bit.
Faint can also mean lacking courage or strength. If someone accuses you of being faint of heart or faint-hearted, they're suggesting you give up too easily when things get difficult or scary.