What is a stroke, as on a door for admittance; a rap. " A knock at the door." Longfellow. A loud cry or some great knock. Holland. Knock off, a device in a knitting machine to remove loops from the needles called?

knock — A stroke, as on a door for admittance; a rap. " A knock at the door." Longfellow. A loud cry or some great knock. Holland. Knock off, a device in a knitting machine to remove loops from the needles. (Webster's 1913.)