[Elamur Dictionary](https://md.dictionary.elamur.ai/free/en/) · [this page in HTML](https://dictionary.elamur.ai/free/en/english/cog/)

[dictionaries](https://md.dictionary.elamur.ai/free/en/) / [English](https://md.dictionary.elamur.ai/free/en/english/) / [C](https://md.dictionary.elamur.ai/free/en/english/c/) / cog

# cog

noun (a cog, cogs)

«cog» in the English dictionary: everyday — its meanings, how the lessons use it, and examples, each with its tree on Mova.

## Everyday

1. A cog is one of the teeth around the edge of a wheel in a machine; a whole wheel with teeth is also called a cog or cogwheel (gear). [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#m1)
2. (figurative) «A cog in the machine» is a person who has a small part in a big organisation and feels unimportant. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#m2)
3. (UK, slang) In some places, «to cog» means to copy someone's homework. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#m3)

### In the lessons

In science and DT lessons, cogs (gears) show how turning one wheel can turn another faster, slower or the other way; a small cog turning a big cog makes it turn more slowly but with more force. In stories, «the cogs were turning» means someone was thinking hard. Phrases: «a cog in the machine», «cogs turning», «cogwheel».

### Examples

- The clock's cogs turned slowly behind the glass. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#x1)
- When the big cog turns once, the small cog turns three times. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#x2)
- A missing tooth on the cog jammed the machine. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#x3)
- You could see the cogs turning in his head as he worked out the puzzle. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#x4)
- He felt like a tiny cog in a huge company. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#x5)
- We built a cog model from cardboard and pins. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#x6)
- The bike's chain runs over cogs at the back wheel. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/#x7)

### Note

Countable noun: one cog, two cogs. In maths problems with gears, if a big cog has 30 teeth and a small one 10, the small cog turns 3 times for each turn of the big one (30 ÷ 10 = 3).

## On Mova

- [Trees and pragmatics of «cog» in the school dictionary](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/cog/): every meaning and example parsed by Mova, with its dependency tree and frames.
- [«cog» in the school dictionary](https://mova.elamur.ai/free/en/dictionaries/school/w/cog.html) on Mova free.