# build up

CEFR B1 · Phrasal verb

Source: https://englishreference.com/word/build-up
Updated: 2026-10-22

## Definition

To increase or develop something gradually over time. You use this when you want to make something stronger, bigger, or better.

For teachers: To increase, strengthen, or develop something by gradual increments. The verb functions transitively when an agent creates the increase and intransitively when a substance or force accumulates.

## Examples

- You need to build up your confidence for the job interview.
- The athlete spent months in the gym to build up her muscle mass before the Olympic trials.
- The company aims to build up its cash reserves to ensure long-term stability during the upcoming economic downturn.

## Pitfalls

- Not "The traffic is building itself up." but "The traffic is building up." — When describing accumulation like traffic or pressure, the verb is intransitive and does not take a reflexive pronoun.

## Usage notes

- Often used with abstract nouns like 'confidence', 'strength', or 'pressure'.
- Teaching tip: Contrast with 'increase' (more formal) and 'accumulate' (often used for negative things like debt or dirt).

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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.