# fill out

Source: https://englishreference.com/word/fill-out
Updated: 2026-08-08

## Senses

### 2. to become larger or heavier

phrasal verb · CEFR B2

to become larger, stronger, or heavier as you grow up.

For teachers: to develop a more substantial or rounded physique, typically through physical maturation or weight gain.

- He was very thin as a child, but he started to fill out in his late teens.
- After a summer of intensive training and a disciplined diet, the young athlete began to fill out, gaining the muscle mass needed for the senior league.

Usage: This sense is intransitive and does not take a direct object.

## Examples

- Please fill out this form with your name and address.
- You need to fill out the application carefully before you submit it to the office.
- The patient was requested to fill out a comprehensive medical history questionnaire prior to their initial consultation with the specialist.

## Usage notes

- Teaching tip: contrast with 'fill in' (British English preference) and 'fill up' (used for containers like a glass or a gas tank); 'fill out' is the standard American term for documents.

---

From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.