Man’s best friend vs Pet

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

Man’s best friend

Top 3,000 (common)

Pet

Top 1,000 (very common)A2noun
Most common: Pet
 Man’s best friendPet
Pronunciation🇬🇧 //mænz bɛst frɛnd//🇺🇸 //mænz bɛst frɛnd//🇬🇧 /["/pet/"]/🇺🇸 /["/pet/"]/
MeaningA dog, often seen as a loyal companion.An animal kept for companionship.
ExampleEverybody says that a dog is man’s best friend.I have a pet dog named Rufus.
RegisterNeutralNeutral
How commonTop 3,000 (common)Top 1,000 (very common)
CEFR level-A2
Part of speechnoun
Collocationsloyal companion, play fetch, dog training, pet owner, heartfelt bonddomestic, family, house, have, keep, own, shop, store, cat
Antonyms-wild animal, stray
Common mistakesConfusing the phrase with other pets like cats., Using it to describe relationships with non-animals., Forgetting that it refers specifically to dogs.Confused with 'pest', thinking they are the same., Using 'pet' as a verb incorrectly outside of its appropriate context., Incorrectly pluralizing with 'pets' when talking about a single pet.
Usage notesTypically used in informal contexts to express the close relationship between dogs and humans. It is often said with affection.Use 'pet' to refer to domestic animals. It's neutral and widely used in conversation. Avoid using it in formal writing where more specific terms might be required.

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Man’s best friend
Pet

Frequently asked questions: Man’s best friend vs Pet

What's the difference between Man’s best friend and Pet?

Man’s best friend: A dog, often seen as a loyal companion. Pet: An animal kept for companionship.

Which is more common: Man’s best friend and Pet?

Pet is the most common in everyday English.

Can you show an example of each?

Man’s best friend: Everybody says that a dog is man’s best friend. Pet: I have a pet dog named Rufus.

Can I use Man’s best friend and Pet interchangeably?

Not always. Man’s best friend and Pet 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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