Longman Dictionary of Contemporary English
Wiktionary
n. A device used to help the hard of hearing to hear sounds.
WordNet
n. an electronic device that amplifies sound and is worn to compensate for poor hearing [syn: deaf-aid]
a conical acoustic device formerly used to direct sound to the ear of a hearing-impaired person [syn: ear trumpet]
Wikipedia
Earlier devices, such as ear trumpets or ear horns, were passive amplification cones designed to gather sound energy and direct it into the ear canal. Modern devices are computerised electroacoustic systems that transform environmental sound to make it more intelligible or comfortable, according to audiometrical and cognitive rules. Such sound processing can be considerable, such as highlighting a spatial region, shifting frequencies, cancelling noise and wind, or highlighting voice.
Modern hearing aids require configuration to match the hearing loss, physical features, and lifestyle of the wearer. This process is called "fitting" and is performed by audiologists. The amount of benefit a hearing aid delivers depends in large part on the quality of its fitting. Devices similar to hearing aids include the bone anchored hearing aid, and cochlear implant.
Usage examples of "hearing aid".
The ventilator-the ventilator we used as a hearing aid, the one facing the radio room.
Leathery, wizened, a bulky hearing aid in his ear, his thin lipless lower jaw thrust out over a corded, wattled neck, he looked a bit like an angry tortoise.
An old man testified that a man who looked like Wilson had bought a hearing aid from him for $239.
The public address system interferes with my hearing aid,' he said.
Even now, after all, there was that pinstriped collarless shirt and the silvery slant of hair, those perfect teeth glinting between the thin Peck lips, the waxy gray cord of his hearing aid and the deep-socketed eyes, closed but still leaking their blueness into the white of the lids.
He had large hands, I noticed, full fleshed, with pale skin, and as he bent his head over the paper I saw the discreet pink hearing aid tucked behind his right ear, below the frame of his glasses.
Polly's raven hair swung wide, and when it uncovered her right ear for an instant, she was almost certainly wearing a tiny, almost invisible hearing aid.
Matt, guessed he'd been caught wearing a hearing aid or something.
That one that's like the hearing aid, except that it doesn't work.