fill out

phrasal verb·3 senses·particle out

Usefulness
Registerspokenbusiness

Meanings

1

Complete a form by writing in the required information

Why “out”? Something comes into the open. People can see it, know it, or understand it.

Please fill out this form.
Please complete this form by writing in the details.
Fill out the tax form online.
Complete the tax form by writing in the details online.
Leo filled out the registration form at the seaside hotel.
Leo completed the registration form by writing the required details at the seaside hotel.
2

Become rounder or more developed in shape

Expansionuncommon

Why “out”? Something spreads, grows, or extends beyond its first size, shape, or path.

He's filled out since school.
His body has become broader since school.
The puppy filled out over winter.
The puppy became rounder and more developed over winter.
3

Add details to make something more complete

Fill out the introduction with examples.
Add details and examples to the introduction.
Add stories to fill out the chapter.
Add stories to make the chapter more complete.

Common mistake

I filled the application.

I filled out the application.

Complete a form = fill out (US) or fill in (UK).

Natural collocations

The word partners “fill out” most often appears with — learn the phrase, not just the verb.

fill out an applicationfill out a questionnairefill it out

Don't confuse with

fill outfill in

Fill out means complete a form by writing in the required information. Fill in means write information into the blanks of a form.

fill outfill up

Fill out means complete a form. Fill up means make something completely full.

Test yourself

Please fill out this form. What does it mean?

Nearby in the meaning map

Sink In connects verbs by particle pattern, contrast pairs, and shared base verbs.

Tell it apart

Side-by-side comparisons with the verbs learners most often confuse for “fill out”.

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