# chaos

/ˈkeɪɑs/ (US) · /kˈeɪɒs/ (UK)

Source: https://englishreference.com/word/chaos
Updated: 2026-06-19

## Senses

### 1. total confusion

noun · CEFR B2

a situation where everything is happening at once and there is no order.

For teachers: a state of utter confusion or disorder; a total lack of organization or predictability.

- The station was in total chaos after all the trains were cancelled.
- The sudden withdrawal of funding threw the entire research department into a state of chaos, leaving dozens of projects unfinished.

### 2. complex systems

noun · CEFR C1 · Technical

a type of math or science where very small changes can lead to huge, unpredictable results.

For teachers: the property of a complex system where small variations in initial conditions result in massive differences in later states.

- Weather is a great example of chaos because a tiny change in wind can change a whole storm.
- In mathematics, chaos describes systems that appear random but are actually governed by sensitive, non-linear laws.

Usage: Often used in the phrase 'chaos theory'.

### 3. mythology

noun · CEFR C2 · Literary · Academic

the empty space or confusion that existed before the world was created in ancient stories.

For teachers: the primordial void or state of matter preceding the creation of the universe in various cosmogonies.

- In ancient Greek myths, the universe began as a dark chaos.
- The poet describes the transition from primordial chaos to the structured harmony of the heavens.

## Examples

- The classroom turned into complete chaos when the teacher left.
- The sudden cancellation of all outbound flights caused absolute chaos at the airport terminals.
- While the mathematician saw an underlying pattern in the data, to the untrained eye the fluctuating numbers appeared as pure, unadulterated chaos.

---

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.