M16

noun

ˌem-(ˌ)sik-ˈstēn How to pronounce M16 (audio)
: a .223 caliber (5.56 millimeter) gas-operated magazine-fed rifle for semiautomatic or automatic operation used by U.S. troops since the mid 1960s

Word History

Etymology

model 16

First Known Use

1968, in the meaning defined above

Time Traveler
The first known use of M16 was in 1968

Browse Nearby Words

M-1
M16
M1 rifle
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Cite this Entry

“M16.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/M16. Accessed 25 May. 2025.

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