To sniffle means to breathe in sharply and loudly through your nose, especially when you have a cold or are trying not to cry. You know that sound when someone's nose is a little stuffed up and they keep making quick sniffing noises? That's sniffling. You might sniffle throughout math class when you're fighting a cold, or sniffle a few times after skinning your knee on the playground.

The word can also be a noun: a sniffle is the sound itself. When you have the sniffles, it means you have a mild cold with a runny or stuffy nose. Someone might tell you they can't come over because they've got the sniffles.

Sniffling sometimes happens when you're trying hard not to cry, that moment when you're holding back tears but your nose gives you away with a few telltale sniffs. Teachers can usually tell when a student is upset partly by hearing those quiet sniffles, even before they see any tears.