# AAS

Source: https://englishreference.com/word/aas
Updated: 2026-05-10

## Senses

### 1. muscle-building drugs

noun · CEFR C1 · Technical

a short name for steroids that people sometimes use to build muscle and improve sports performance.

For teachers: initialism for anabolic-androgenic steroids, synthetic derivatives of testosterone used to promote muscle growth and bone density.

- The athlete was banned after testing positive for AAS during the competition.
- The long-term administration of AAS is associated with significant cardiovascular risks and endocrine disruption in professional bodybuilders.

Usage: Usually treated as an uncountable noun when referring to the class of drugs.

Teaching tip: In fitness and medical contexts, this is the most common meaning of the acronym.

### 2. chemical analysis

noun · CEFR C2 · Technical

a laboratory method used to find out how much of a specific metal is in a sample.

For teachers: initialism for Atomic Absorption Spectroscopy, a spectroanalytical procedure for the quantitative determination of chemical elements.

- The scientists used AAS to check the water for lead and mercury.
- AAS remains a gold-standard technique for detecting trace concentrations of heavy metals within environmental soil samples.

Usage: Uncountable in this scientific sense.

### 3. geometry rule

noun · CEFR C2 · Technical

a rule in math used to prove that two triangles are exactly the same size and shape.

For teachers: initialism for Angle-Angle-Side, a theorem used to prove the congruence of two triangles if two angles and a non-included side are equal.

- We used the AAS rule to solve the geometry problem on the test.
- The student correctly identified that the AAS theorem was sufficient to prove the two triangles were congruent despite the missing side length.

### 4. professional societies

noun · CEFR C1 · Formal

a short name for various groups, like the American Astronomical Society.

For teachers: initialism for several academic and professional organizations, most notably the American Astronomical Society or the Australian Academy of Science.

- She presented her research at the annual AAS meeting in Hawaii.
- The AAS issued a formal statement regarding the impact of satellite constellations on ground-based astronomical observations.

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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.