# AIS

/ˈaɪz/ (US) · /ˈaɪz/ (UK) · CEFR C2 · Noun

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

## Definition

Stands for Automatic Identification System. A tracking system used by ships and traffic controllers to see where boats are and where they are going.

For teachers: Abbreviation for Automatic Identification System. An automated tracking system that uses transponders on ships to provide identity, position, course, and speed data to other vessels and coastal authorities.

## Examples

- The captain checked the AIS to see if any ships were nearby.
- Port authorities use AIS data to manage the flow of traffic and prevent collisions in the busy harbour.
- While radar remains essential for detecting physical obstacles, AIS provides critical digital metadata that allows navigators to identify specific vessels and communicate with them directly via radio.

## Usage notes

- Often used as a modifier before another noun, such as 'AIS data' or 'AIS transponder'.

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