1. the action or sound of hitting something repeatedly
2. a rattling or metallic sound in an engine
Usage: automotive

1. present participle of knock; hitting or striking something

Examples

• She heard knocking at the front door.
• The knocking grew louder and more insistent.
• He was knocking on wood for good luck.
• The mechanic detected knocking in the engine.
• Stop knocking on the table during class.
• The knocking sound woke everyone up.
• They were knocking down the old building.