# algorithm

/ˈæɫɡɝˌɪðəm/ (US) · /ˈælɡəɹˌɪθəm/ (UK)

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

## Senses

### 1. computing/math

noun · CEFR B2 · Technical

a set of step-by-step instructions that a computer follows to complete a task.

For teachers: a precise, finite sequence of instructions or rules designed to perform a specific task or solve a mathematical problem.

- The search engine uses a complex algorithm to find the most relevant websites for you.
- The encryption algorithm ensures that sensitive data remains secure by converting plain text into a complex code that is nearly impossible to crack without the key.

Usage: Often used with verbs like 'develop', 'implement', or 'run'.

### 2. social media/feeds

noun · CEFR B2 · Informal

the system used by social media apps to decide which posts or videos you see first.

For teachers: the automated curation and recommendation systems employed by digital platforms to personalise user experience and maximise engagement.

- I keep seeing cat videos because the algorithm knows I like them.
- Content creators often struggle to adapt their strategies whenever the platform's algorithm changes its criteria for promoting viral videos.

Teaching tip: In casual conversation, people often personify 'the algorithm' as if it has its own intentions or personality.

### 3. decision-making guide

noun · CEFR C1 · Technical · Formal

a chart or list of steps that helps people, like doctors, make a decision.

For teachers: a systematic procedure or flowchart used to guide human decision-making, particularly in clinical or diagnostic contexts.

- The hospital followed a strict algorithm to decide which patients needed immediate surgery.
- The diagnostic algorithm provides a step-by-step framework for clinicians to identify rare autoimmune disorders based on specific patient symptoms.

## Examples

- The app uses an algorithm to suggest new songs you might like.
- To sort the massive database quickly, the engineering team wrote a new algorithm that processes the information in half the time.
- While early algorithms were simple step-by-step instructions for basic calculations, modern machine learning models develop their own complex pathways to predict user behaviour with unsettling accuracy.

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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.