English to English

noun (n)

• someone who performs rap music(noun.person)

  source: wordnet30
• a device (usually metal and ornamental) attached by a hinge to a door(noun.artifact)

  Synonym:
  doorknocker, knocker
  

  source: wordnet30
• One who, or that which, raps or knocks; specifically, the knocker of a door.(noun)

  source: webster1913