Attachment vs File

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

Attachment

Top 1,000 (very common)B2noun

File

Top 1,000 (very common)B1noun
 AttachmentFile
Pronunciation🇬🇧 /["/əˈtætʃmənt/"]/🇺🇸 /["/əˈtætʃmənt/"]/🇬🇧 /["/faɪl/"]/🇺🇸 /["/faɪl/"]/
MeaningSomething that is connected or added to something else.A collection of information or documents stored together.
ExampleNo attachment was included.Please upload the file to the system.
RegisterNeutralNeutral
How commonTop 1,000 (very common)Top 1,000 (very common)
CEFR levelB2B1
Part of speechnounnoun
Collocationsemail, unsolicited, infected, include, send, open, close, deep, passionate, feel, have, develop, attachment tobulging, bulky, thick, box, stack, have, keep, maintain, contain something, cabinet, drawer, folder, in a/​the file, on file, file on, large, computer, digital, directory, list, set, create, download, upload, contain something, name, format, size, in a/​the file, bulging, bulky, thick, box, stack, have, keep, maintain, contain something, cabinet, drawer, folder, in a/​the file, on file, file on
Antonymsdetachment, separationdisorder, chaos
Common mistakes'Attachment' incorrectly used as a verb., 'Attachment' confused with 'attachment style' in psychological contexts., Mispronouncing 'attachment' as 'attach-ment' instead of 'at-tach-ment'.Confused about whether 'file' is a noun or a verb., Using 'files' when referring to a single document., Incorrectly spelling as 'fyle' or 'fihl'.
Usage notesUse 'attachment' in a variety of contexts, like emails (an attached file) or emotional connections. Avoid using it in very casual settings where a simpler word would suffice.Used in both physical and digital contexts. In formal contexts, use 'document' or 'record' for specificity. Avoid using 'file' to refer to a single item unless specified.

Frequently asked questions: Attachment vs File

What's the difference between Attachment and File?

Attachment: Something that is connected or added to something else. File: A collection of information or documents stored together.

Are Attachment and File the same CEFR level?

Attachment: B2, File: B1 on the CEFR scale.

Can I use Attachment and File interchangeably?

Not always. Attachment and File 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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