knock on

1 of 3

transitive verb

: 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

knock-on

2 of 3

noun

plural knock-ons

: the action of knocking on

knock-on

3 of 3

adjective

"

: 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

Word History

Etymology

Noun

knock on

Adjective

knock on

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