make (someone) unable to breathe properly; suffocate

those in the streets were stifled by the fumes

restrain (a reaction) or stop oneself acting on (an emotion)

she stifled a giggle

he stifled a desire to turn and flee

she gave a stifled cry of disappointment

(of heat, air, or a room) very hot and causing difficulties in breathing; suffocating

stifling heat

the loft is stifling in summer

making one feel constrained or oppressed

the stifling formality of her family life