What is the meaning of narrowing?

noun

• An instance of becoming narrow.
• A decrease in width.
• The act of making something narrower.

verb

• Make or become more narrow or restricted.
  • usage: "The selection was narrowed"; "The road narrowed"
  • synonyms: narrow, contract
• Define clearly.
  • usage: "I cannot narrow down the rules for this game"
  • synonyms: pin down, peg down, nail down, narrow down, narrow, specify
• Become more focus on an area of activity or field of study.
  • usage: "She specializes in Near Eastern history"
  • synonyms: specialize, specialise, narrow, narrow down
• Become tight or as if tight.
  • usage: "Her throat constricted"
  • synonyms: constrict, constringe, narrow

adjective

• Becoming gradually narrower.
  • usage: "long tapering fingers"; "trousers with tapered legs"
  • synonyms: tapered, tapering
• Of circumstances. ( tending to constrict freedom).
  • synonyms: constricting, constrictive