Effectiveness vs Success

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

Effectiveness

Top 2,000 (common)C1noun

Success

Top 1,000 (very common)A1noun
Most common: Success
 EffectivenessSuccess
Pronunciation🇬🇧 /["/ɪˈfektɪvnəs/","/ɪˌfekˈtɪvəti/"]/🇺🇸 /["/ɪˈfektɪvnəs/","/ɪˌfekˈtɪvəti/"]/🇬🇧 /["/səkˈses/"]/🇺🇸 /["/səkˈses/"]/
MeaningHow well something works or succeeds.When you achieve something you wanted to do.
Exampleto check the effectiveness of the security systemHis success in the competition made him very proud.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 1,000 (very common)
CEFR levelC1A1
Part of speechnounnoun
Collocationsmeasure effectiveness, assess effectiveness, improve effectiveness, evaluate effectivenessenormous, great, immense, amount, degree, level, achieve, attain, enjoy, come, lie (in something), depend on something, rate, story, factor, with success, without success, success in, a chance of success, a hope of success, confident of success, resounding, roaring, rousing, be, prove, have, wish somebody (every) success
Antonymsineffectiveness, failurefailure, defeat, setback
Common mistakesConfused with 'effect' — remember 'effect' is a noun meaning the result., Using 'effectiveness' when discussing personal feelings — it's more about objective results., Mispronouncing the word, often stressing the wrong syllable.Confused with 'successfully', which is an adverb., Used incorrectly as a verb instead of the noun form., Misplaced in sentences, such as 'We have success' instead of 'We are successful'.
Usage notesUsed in both formal and informal contexts, often in discussions of strategies, programs, or methods. Avoid using in overly casual conversations.Use 'success' when talking about achieving goals or winning in a friendly context. Avoid using it in negative situations or as a mockery.

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Success

Frequently asked questions: Effectiveness vs Success

What's the difference between Effectiveness and Success?

Effectiveness: How well something works or succeeds. Success: When you achieve something you wanted to do.

Which is more common: Effectiveness and Success?

Success is the most common in everyday English.

Which is more advanced: Effectiveness and Success?

Effectiveness is the highest level, at C1, on the CEFR scale.

Are Effectiveness and Success the same CEFR level?

Effectiveness: C1, Success: A1 on the CEFR scale.

What part of speech are Effectiveness and Success?

Effectiveness: noun, Success: noun.

Can you show an example of each?

Effectiveness: to check the effectiveness of the security system Success: His success in the competition made him very proud.

Can I use Effectiveness and Success interchangeably?

Not always. Effectiveness and Success 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.

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