Whiff means to smell something briefly, or to fail completely at hitting or catching something.

When you walk past a bakery and catch a whiff of fresh bread, you've gotten a quick, passing smell. A whiff is a light, fleeting scent rather than something you deeply breathe in: you might get a whiff of smoke from a distant campfire or a whiff of perfume when someone walks by. The word captures that fleeting moment when a scent reaches your nose and then disappears.

In sports, whiff takes on a different meaning: it's when you swing at a ball and miss it entirely. A baseball player whiffs when his bat cuts through empty air instead of connecting with the pitch. A tennis player might whiff on an easy serve. The word perfectly captures that embarrassing whoosh of hitting nothing.

You can also use whiff more generally for any complete failure to connect with something. If you whiff on a test question, you missed it badly. If someone takes a whiff at guessing your age, they got it totally wrong. The word suggests missing in an obvious, almost comical way, like swinging at air.