# DIA

/ˈdiə/ (US) · CEFR A1 · Noun

Source: https://englishreference.com/word/dia
Updated: 2026-05-06

## Definition

a single period of twenty-four hours. You use this to talk about time, dates, or the light part of the 24-hour cycle.

For teachers: a period of twenty-four hours as a unit of time, or the interval of light between sunrise and sunset.

## Pitfalls

- Not "I go to the gym everyday." but "I go to the gym every day." — 'Everyday' is an adjective meaning ordinary; 'every day' is the adverbial phrase meaning each day.

## Usage notes

- Commonly used in the phrase 'every day' (two words) as an adverbial phrase of frequency.

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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.