# ATP

/ˈeɪˈtiˈpi/ (US) · CEFR C2 · Noun

Source: https://englishreference.com/word/atp
Updated: 2026-05-09

## Definition

Stands for Adenosine Triphosphate. A molecule that carries energy inside the cells of all living things. It acts like a tiny battery that powers everything your body does, from moving muscles to thinking.

For teachers: Abbreviation for Adenosine Triphosphate. An organic compound that provides energy to drive many processes in living cells, such as muscle contraction and nerve impulse propagation. Often described as the 'molecular unit of currency' of intracellular energy transfer.

## Examples

- Cells use ATP to power their daily activities.
- During intense exercise, your muscles quickly burn through their stored ATP and must create more to keep moving.
- The mitochondria are often called the powerhouses of the cell because they are the primary sites where ATP is synthesized through the process of oxidative phosphorylation.

## Usage notes

- Usually treated as uncountable when referring to the chemical substance; can be countable in technical contexts referring to specific molecules.

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