# nucleotide

/ˈnukɫiəˌtaɪd/ (US) · /njˈuːklɪˌɒtaɪd/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/nucleotide
Updated: 2026-05-18

## Definition

a small chemical unit that is the basic building block of DNA and RNA. These units join together to form the long strands that carry genetic information.

For teachers: a monomer consisting of a nitrogenous base, a sugar, and a phosphate group, which serves as the fundamental unit of nucleic acids. Each nucleotide contributes to the genetic code through its specific base pairing.

## Examples

- Each nucleotide contains a sugar, a phosphate, and a base.
- Scientists identified a specific nucleotide sequence that was responsible for the mutation in the virus.
- The precise arrangement of nucleotides along the DNA helix determines the genetic instructions for protein synthesis and cellular function.

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