Smoothbore musket

A musket is a muzzle-loaded, smoothbore long gun that appeared in early 16th century Europe, at first as a heavier variant of the arquebus capable of penetrating heavy armor. By the mid-16th century, this type of musket went out of use as heavy armor declined, but as the matchlock became standard, the term musket continued as the name given for any long gun with a flintlock, and then its successors, all the way through the mid 1800s. This style of musket was retired in the 19th century when rifled muskets (technically rifles, but still referred to as muskets) became common as a result of cartridged breech-loading firearms introduced by Casimir Lefaucheux in 1835, the invention of the Minié ball by Claude-Étienne Minié in 1849, and the first reliable repeating rifle produced by Volcanic Repeating Arms in 1854. By the time repeating rifles became common, they were known as simply "rifles", ending the era of the musket.

According to the Etymology Dictionary, firearms were often named after animals, and the word musket derived from the French word mousquette, which is a male sparrowhawk. An alternative theory is that derives from the 16th century French mousquet, -ette, from the Italian moscetto, -etta, meaning the bolt of a crossbow. The Italian moscetto is a diminutive of mosca, a fly.

The first recorded usage of the term "musket" or moschetto appeared in Europe in the year 1499. Evidence of the musket as a type of firearm does not appear until 1521 when it was used to describe a heavy arquebus capable of penetrating heavy armor. This version of the musket fell out of use after the mid-16th century with the decline of heavy armor, however the term itself stuck around as a general descriptor for 'shoulder arms' fireweapons into the 1800s. The differences between the arquebus and musket post-16th century are therefore not entirely clear, and the two have been used interchangeably on several occasions.

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