physically unable to hear anything or unable to hear well [↪ hearing impaired]:
communication between deaf and hearing people
I think Mum's going a bit deaf.
She's deaf and dumb (=unable to hear or speak) and communicates using sign language.
Tom was born profoundly deaf (=completely deaf).
stone deaf/deaf as a post informal (=completely deaf)➔ hard of hearing, tone-deaf
people who are deaf:
a school for the deaf
to be unwilling to hear or listen to something:
She was deaf to his pleas.
to be unwilling to listen to what someone is saying or asking:
The factory owners turned a deaf ear to the demands of the workers.
if advice or a warning falls on deaf ears, everyone ignores it
—deafness noun [uncountable]