Fat vs Grease

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

Fat

Top 2,000 (common)A1adjective

Grease

Top 2,000 (common)
 FatGrease
Pronunciation🇬🇧 /["/fæt/"]/🇺🇸 /["/fæt/"]/🇬🇧 //ɡriːs//🇺🇸 //ɡriːs//
MeaningHaving a lot of body weight; not thin.A thick, oily substance used for lubrication.
ExampleThe fat cat slept on the windowsill.The mechanic applied grease to the engine to ensure smooth operation.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 2,000 (common)
CEFR levelA1-
Part of speechadjective
Collocationsbe, feel, look, enormously, hugely, immensely, big fat, be, feel, look, enormously, hugely, immensely, big fatapply grease, grease maintenance, cooking grease, grease the wheels, grease trap
Antonymsthin, slim, skinnydry
Common mistakesUsing 'fat' to describe a person in a derogatory manner., Confusing 'fat' with 'overweight'; 'fat' is often viewed as more judgmental., Using 'fats' instead of 'fat' when describing body shape.Confused with 'greased' as a past form., Using 'grease' as a verb incorrectly, e.g., 'I grease for my bike.'
Usage notesUsed to describe someone who has excess body weight. Avoid using this word to describe someone in a negative or derogatory way, as it can be considered offensive.Used in mechanical contexts or cooking. Not commonly used in formal writing. Can describe a substance or a process.

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Grease

Frequently asked questions: Fat vs Grease

What's the difference between Fat and Grease?

Fat: Having a lot of body weight; not thin. Grease: A thick, oily substance used for lubrication.

Can you show an example of each?

Fat: The fat cat slept on the windowsill. Grease: The mechanic applied grease to the engine to ensure smooth operation.

Can I use Fat and Grease interchangeably?

Not always. Fat and Grease 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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