catch a whiff of (something)

1. Literally, to detect a faint odor or scent. Yuck, I just caught a whiff of dog poop. Did you step in some on the way home? I think I'm catching a whiff of garlic from the broth—is that correct? On a warm, breezy day like this, you're sure to catch a whiff of the flowers from the neighbor's garden.

2. To receive an extremely small portion or sample of something desirable. Health insurance, a company phone, and a pension plan? Man, I didn't catch a whiff of benefits like those when I was working for the company. He didn't patent the design, so he won't catch a whiff of the money they're making on it. I left that job after I didn't catch a whiff of a raise in five years.

3. To receive a very small amount of information, especially just enough to give someone an indication or inkling of something. Make sure you don't let the boss catch a whiff of what you're trying to do, or you'll get fired so fast your head will spin! Detective Matheson says he's caught a whiff of something going down at the docks tomorrow night. Sounds like it could be a major drug deal. If you keep acting weird like that, Mom will catch a whiff of our plans to sneak out and go to the party.