# zeta

/ˈzeɪtə/ (US) · /zˈɛtɐ/ (UK) · CEFR C2 · Noun

Source: https://englishreference.com/word/zeta
Updated: 2026-05-31

## Definition

the sixth letter of the Greek alphabet. In math and science, it is often used as a symbol for a specific number or a variable.

For teachers: the sixth letter of the Greek alphabet (Ζ, ζ). In mathematical contexts, it frequently represents the Riemann zeta function or specific angles in physics and engineering.

## Examples

- The professor used the letter zeta to label the angle in the diagram.
- In advanced calculus, students learn how the zeta function relates to the distribution of prime numbers.
- The researcher noted that the zeta potential of the particles remained stable, indicating that the suspension would not settle or clump over time.

## Usage notes

- When referring to the Greek letter, it is a countable noun; when referring to the Riemann zeta function, it is often used as a proper noun or with the definite article.

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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.