hearing aid

Từ điển WordNet v3.1 - WordNet Dictionary

noun

1. an electronic device that amplifies sound and is worn to compensate for poor hearing
• Syn:
deaf-aid
• Hypernyms:
electronic device
2. a conical acoustic device formerly used to direct sound to the ear of a hearing-impaired person
• Syn:
ear trumpet
• Hypernyms:
acoustic device