Meaning

• Sudden fatigue as a result of glycogen depletion from not having taken in enough nutrition.

Meaning

• An abrupt rapping sound, as from an impact of a hard object against wood.

  "I heard a knock on my door."

• A sharp impact.

  "He took a knock on the head."

• Criticism.

• Preignition, a type of abnormal combustion occurring in spark ignition engines caused by self-ignition; also, the characteristic knocking sound associated with it.

• A batsman's innings.

  "He played a slow but sure knock of 35."

Meaning

• To strike for admittance; to rap upon, as a door.

• To criticize verbally; to denigrate; to undervalue.

  "Don’t knock it until you’ve tried it."

• To kick a ball towards another player; to pass.

• To impress forcibly or strongly; to astonish; to move to admiration or applause.

• To bump or impact.

  "I accidentally knocked my drink off the bar."

• To rap one's knuckles against something, especially wood.

  "Knock on the door and find out if they’re home."