Stifling means so hot, stuffy, or airless that it feels hard to breathe comfortably. A classroom on a sweltering June afternoon with broken air conditioning becomes stifling. When you open the door to an attic that's been closed up all summer, you might gasp at the stifling heat that pours out.

The word captures that oppressive feeling when the air seems thick and heavy. A stifling room makes you want to throw open windows or escape outside. You might loosen your collar or fan yourself, desperate for fresh air.

Stifling also describes situations that prevent freedom, creativity, or growth. A teacher who never lets students ask questions creates a stifling classroom environment. Rules can be stifling if they're so strict they crush all creativity and fun. When a friend's parents are so overprotective that they won't let her make any decisions on her own, that control can feel stifling.

In both uses, something stifling holds you back or weighs you down. Whether it's heat that makes breathing difficult or restrictions that prevent you from being yourself, stifling describes conditions that feel suffocating and unbearable.