What is the meaning of winnow?

noun

• The act of separating grain from chaff.
  • usage: "the winnowing was done by women"
  • synonyms: winnowing, sifting

verb

• Separate the chaff from by using air currents.
  • usage: "She stood there winnowing chaff all day in the field"
  • synonyms: fan
• Blow on.
  • usage: "The wind was winnowing her hair"; "the wind winnowed the grass"
• Select desirable parts from a group or list.
  • usage: "cull out the interesting letters from the poet's correspondence"; "winnow the finalists from the long list of applicants"
  • synonyms: cull out
• Blow away or off with a current of air.
  • usage: "winnow chaff"