Effect vs Knock-on

When to use each in English, with meaning, register, and examples.

Effect

Top 1,000 (very common)A2noun

Knock-on

Top 3,000 (common)
Most common: Effect
 EffectKnock-on
Pronunciation🇬🇧 /["/ɪˈfekt/"]/🇺🇸 /["/ɪˈfekt/"]/🇬🇧 //nɒk ɒn//🇺🇸 //nɑk ɑn//
MeaningA change that is caused by something.A result or effect from an action.
ExampleThe effect of the medicine was noticeable within hours.The new law had a significant knock-on effect on the economy.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 3,000 (common)
CEFR levelA2-
Part of speechnoun
Collocationsdecisive, dramatic, far-reaching, bring about, exert, have, exist, occur, spread, in effect, to this effect, to that effect, cause and effect, to little effect, to no effect, special, cinematic, audioknock-on effect, knock-on consequences, knock-on impact
Antonymscause, source-
Common mistakesConfused with 'affect' versus 'effect'., Using 'effect' as a verb instead of a noun., Confusing singular and plural forms (e.g., 'effects' vs 'effect').Using 'knock-on' without a noun afterwards., Confusing it with similar phrases like 'knock-off'.
Usage notesUse 'effect' to refer to results or changes. It's more formal than 'result.' Avoid using it where 'affect' (to influence) fits better.Often used in discussions about consequences or effects of actions. Suitable for both spoken and written contexts.

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Effect

Frequently asked questions: Effect vs Knock-on

What's the difference between Effect and Knock-on?

Effect: A change that is caused by something. Knock-on: A result or effect from an action.

Which is more common: Effect and Knock-on?

Effect is the most common in everyday English.

Can you show an example of each?

Effect: The effect of the medicine was noticeable within hours. Knock-on: The new law had a significant knock-on effect on the economy.

Can I use Effect and Knock-on interchangeably?

Not always. Effect and Knock-on are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.