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C4

British  

noun

  1. a type of plastic explosive

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of C4

C20: from C(omposition) 4

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

A red Seat Leon collided with a Citroen C4 Picasso, driven by Masrob Ali, at about 00:45 GMT.

From BBC Jan. 12, 2026

The key to effective defense, experts say, lies in the C4 layer—short for command, control, computing and communication—which identifies intruders and quickly determines the best response.

From The Wall Street Journal Oct. 18, 2025

His car, a grey-coloured Citroen C4 was found parked in the layby on the A675, near to Tockholes Road.

From BBC Mar. 24, 2025

But on the molecular level, what made C3 plants turn into C4 plants?

From Science Daily Nov. 20, 2024

So even though they both add an F, a C4 suspension36 will sound quite different from a C1137 extended chord.

From "Understanding Basic Music Theory" by Catherine Schmidt-Jones and Russel Jones

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