A barque, barc, or bark is a type of sailing vessel with three or more masts having the fore- and mainmasts rigged square and only the mizzen (the aftmost mast) rigged fore-and-aft.

The word barque entered English via French, which in turn came from the Latin barca by way of Occitan, Spanish or Italian.

The Latin barca may stem from Celtic "barc" (per Thurneysen) or Greek "baris" (per Diez), a term for an Egyptian boat. The Oxford English Dictionary, however, considers the latter improbable.

The word barc appears to have come from Celtic languages. The form adopted by English, perhaps from Irish, was bark, while that adopted by Latin as barca very early, which gave rise to the French barge and barque.

In Latin, Spanish and Italian the term barca refers to a small boat, not a full-size ship. French influence in England led to the use in English of both words, although their meanings now are not the same.

Well before the 19th century a barge had become interpreted as a small vessel of coastal or inland waters. Somewhat later, a bark became a sailing vessel of a distinctive rig as detailed below. In Britain, by the mid-19th century, the spelling had taken on the French form of barque. Although Francis Bacon used this form of the word as early as 1592, Shakespeare still used the spelling "barke" in Sonnet 116 in 1609. Throughout the period of sail, the word was used also as a shortening of the barca-longa of the Mediterranean Sea.

The usual convention is that spelling barque refers to a ship and bark to tree hide, to distinguish the homophones.

"Barcarole" in music shares the same etymology, being originally a folk song sung by Venetian gondolier and derived from barca - boat in Italian.