noun

• (anatomy) In humans, the joint or the region of the joint in the middle part of the leg between the thigh and the shank.
  "Penny was wearing a miniskirt, so she skinned her exposed knees when she fell."
• In birds:
• (shipbuilding) A piece of timber or metal formed with an angle somewhat in the shape of the human knee when bent.
  "Deck beams were supported by hanging knees, triangular pieces of wood typically found underneath the timbers they are designed to support, but in this case found above them."
• (archaic) An act of kneeling, especially to show respect or courtesy.
  "Give them title, knee, and approbation."

verb

• (transitive, archaic) To kneel to.
  "I could as well be brought / To knee his throne and, squire-like, pension beg / To keep base life afoot"
• (transitive) To poke or strike with the knee.
  "When I blocked her from leaving, she kneed me in the groin."
• (reflexive) To move on the knees; to use the knees to move.
  "Hassan kneed himself up, over, in, soundlessly, feet on floor, knife out, eyes like blunter knife trying to cut darkness."