Definition of knock on

 (Entry 1 of 3)

: to knock onward : knock forward specifically : to knock (the ball in rugby) forward in the direction of the opponents' dead-ball line with the hand or arm


plural knock-ons

Definition of knock-on (Entry 2 of 3)

: the action of knocking on


\ " \

Definition of knock-on (Entry 3 of 3)

: produced or projected as a result of the collision of an energetic particle (as a neutron or fission fragment) from outside an atom with an elementary particle inside a knock-on shower of particles a knock-on atom a knock-on electron

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History and Etymology for knock on


knock on


knock on

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Cite this Entry

“Knock on.” The Dictionary, Merriam-Webster Inc., Accessed 13 December 2019.

More from Merriam-Webster on knock on

Nglish: Translation of knock on for Spanish Speakers

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easily led, controlled, or managed

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