Mediocre vs Not so good

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

Mediocre

Top 2,000 (common)B1adjective

Not so good

Top 2,000 (common)
 MediocreNot so good
Pronunciation🇬🇧 //ˌmiː.dɪˈəʊ.kər//🇺🇸 //ˌmiː.dɪˈoʊ.kɚ//🇬🇧 //nɒt səʊ ɡʊd//🇺🇸 //nɑt soʊ ɡʊd//
MeaningNot very good or bad; just okayNot great or satisfactory.
ExampleThe movie received mediocre reviews from critics.After the meeting, I felt that the outcome was not so good.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 2,000 (common)
CEFR levelB1-
Part of speechadjective
Collocationsmediocre performance, mediocre quality, mediocre skillsfeel not so good, look not so good, be not so good, become not so good
Antonymsexcellent, superb, outstanding-
Common mistakesUsed interchangeably with 'average', which can be misleading in context., Confused with 'mediocrity', which is a noun., Overused in casual conversation, leading to a lack of impact.Using it in a positive context., Confusing with 'okay'., Overusing in professional settings.
Usage notesTypically used to describe performance, quality, or skill. Best avoided in formal contexts when possible; may be too negative in some situations.Common in informal conversations when expressing dissatisfaction or disappointment. Avoid in formal writing or speech.

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Not so good

Frequently asked questions: Mediocre vs Not so good

What's the difference between Mediocre and Not so good?

Mediocre: Not very good or bad; just okay Not so good: Not great or satisfactory.

Can you show an example of each?

Mediocre: The movie received mediocre reviews from critics. Not so good: After the meeting, I felt that the outcome was not so good.

Can I use Mediocre and Not so good interchangeably?

Not always. Mediocre and Not so good 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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