# ACS

CEFR C2 · Noun

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

## Definition

a system in a car or machine that helps it stay stable and safe while moving. It uses sensors to monitor how the vehicle is behaving and makes small adjustments automatically.

For teachers: an automated mechanism designed to maintain the stability or safety of a mechanical system, such as a vehicle or aircraft. Often refers to Active Control Systems or Advanced Control Systems in engineering contexts.

## Examples

- The car's ACS helps prevent skidding on wet roads.
- Engineers integrated a new ACS into the drone to ensure it remains level during high-speed maneuvers in turbulent winds.
- The implementation of a sophisticated ACS allows the aircraft to compensate for structural damage in real-time, maintaining flight envelopes that would otherwise be impossible for a human pilot to manage.

## Usage notes

- Often used as an acronym in technical documentation; the specific meaning depends on whether the context is automotive, aerospace, or medical.

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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.