cam

cam — noun

1. an everyday short form of 'camera' — typically a compact, fixed-position digital

1.nounB1
Definition

an everyday short form of 'camera' — typically a compact, fixed-position digital device that records video or takes photographs, used for security, online calls, or surveillance

Example

A small security cam outside the flat records everyone who comes to the door.

collocation: security cam

Theo switched on his laptop cam before the online class started.

collocation: laptop cam

Common collocations
  • security cam
  • webcam
  • laptop cam
  • traffic cam
  • body cam
  • spy cam
  • cam footage
Synonyms
  • camera

    the full, neutral term; cam is an informal shortening

  • webcam

    a camera that streams video online; more specific than cam

  • security camera

    a camera used for surveillance; the formal term for 'security cam'

Grammar Patterns

cam + is/are + [preposition phrase]

Usage Note

Almost always used in compound nouns that name the type or purpose of the camera (security cam, webcam, traffic cam, body cam). The full word 'camera' is preferred in formal writing.

Common Mistakes

I bought a new cam-corder.
I bought a new camcorder.
'camcorder' is one word, not a compound of 'cam' and 'corder'.
He set up the cam in a formal report.
He set up the camera in a formal report.
'cam' sounds too casual for official documents.

2. a moving piece inside an engine, mounted on a spinning shaft, whose unusual shap

2.nounC1
Definition

a moving piece inside an engine, mounted on a spinning shaft, whose unusual shape pushes other parts up, down, or sideways — it opens and closes the valves at exactly the right moment

Example

The cam rotated once for every two turns of the crankshaft.

technical: cam rotation timing

A worn cam can make an engine run unevenly or lose power.

Common collocations
  • cam lobe
  • cam profile
  • cam and lifters
  • cam timing
  • cam gear
  • cam shaft
  • cam follower
Synonyms
  • camshaft

    the shaft that carries cams; 'cam' is sometimes used to mean the whole shaft

  • cam lobe

    the raised part of a cam that pushes the valve; more precise than 'cam'

Grammar Patterns

cam + verb (rotates, pushes, opens)

Usage Note

Often used as a shortening of 'camshaft' (the shaft that carries cams) rather than referring to an individual cam lobe. In automotive contexts, 'cam' can mean the whole camshaft: 'a high-performance cam' means a high-performance camshaft.

Common Mistakes

The cam in my phone stopped working.
The camera in my phone stopped working.
'cam' in mechanics means engine part, not camera.

3. a category of treatments that sit alongside or outside standard medicine — the s

3.nounC1
Definition

a category of treatments that sit alongside or outside standard medicine — the short form stands for complementary therapy and alternative medicine and covers practices such as acupuncture, herbal remedies, and chiropractic care

Example

Many patients combine standard drugs with CAM treatments like acupuncture.

collocation: CAM treatments

The hospital opened a new centre for CAM therapies such as massage and herbal remedies.

collocation: CAM therapies

Common collocations
  • CAM treatments
  • CAM therapies
  • CAM approaches
  • CAM practitioners
  • CAM research
  • CAM centre
Synonyms
Antonyms
  • conventional medicine

    standard medical treatment taught in most medical schools; opposite of CAM in approach

Grammar Patterns

CAM + is/are + [adjective/noun]

Usage Note

Written in all capitals (CAM) as an initialism — each letter is pronounced separately (/siː eɪ ˈem/). Used mainly in medical and healthcare discussions. Not a spoken abbreviation like 'cam' (camera).

Common Mistakes

I take CAM medicine for my headache.
I use CAM treatments like herbs for my headache.
'CAM' is a category label, not a type of medicine itself.

cam — abbreviation

Word family

Synonym discussion

Sense: noun/1

Cam is an informal shortening of 'camera', most common in compound nouns (security cam, webcam, traffic cam). It is rarely used alone outside casual speech. 'Camera' is the neutral, all-purpose term suitable for any register — from a smartphone camera to a professional film camera. 'Webcam' specifically refers to a camera that streams video over the internet, often built into a laptop or monitor. 'Security camera' (or CCTV camera) is the formal term for surveillance equipment; 'security cam' is its informal counterpart. In writing, choose 'camera' for formal documents and 'cam' only for notes, labels, or casual contexts. For example: 'The bank installed new security cameras' (formal report) vs. 'A dash cam caught the whole thing' (casual story).

cam ↗camera ↗webcam ↗security camera

Common collocations

Nouns

  • security cam
  • traffic cam
  • webcam
  • body cam
  • dash cam
  • laptop cam
  • spy cam
  • cam footage

Etymology

DutchEnglish

The noun 'cam' (engine part) entered English in the late 1700s as a shortening of 'camshaft', which itself comes from Dutch 'kam' meaning 'comb' — referring to the comb-like teeth on a rotating shaft. The informal use of 'cam' for 'camera' appeared in the late 20th century as a casual clipping, similar to 'photo' from 'photograph'. The abbreviations CAM (complementary and alternative medicine) and CAM (computer-aided manufacturing) emerged in the 1970s–1990s as technical acronyms in medical and engineering fields respectively.