When used in a nautical sense, a cutter is:
- a small single-masted vessel, fore-and-aft rigged, with two or more headsails, a bowsprit, and a mast set further back than in a sloop
- a ship's boat, powered by oars, sails or motor, used to carry passengers or light stores
- a small or medium sized armed vessel used by various marine or naval services such as the US Coast Guard.
The open cutter carried aboard naval vessels in the 18th Century was rowed by pairs of men sitting side-by-side on benches. The cutter, with its transom, was broader in proportion compared to the longboat, which had finer lines.
Traditionally the sloop rig was a rig with a single mast located forward of 70% of the length of the sailplan. In this traditional definition a sloop could have multiple jibs on a fixed bowsprit. Cutters had a rig with a single mast more centrally located, which could vary from 50% to 70%of the length of the sailplan, with multiple headsails and a reeving bowsprit. Somewhere in the 1950's or 1960's there was a shift in these definitions such that a sloop only flew one headsail and a cutter had multiple headsails and mast position became irrelevant.
In this modern idiom, then, a cutter is a sailing vessel with more than one head sail and one mast. In a traditional vessel there would normally be also, a bowsprit to carry a jib set flying from the bowsprit end via a traveller (to preserve the ability to reef the bowsprit), while in modern vessels the jib is set from a topmast forestay permanently fixed to the end of a fixed (non-reeving) bowsprit, or directly to the stem fitting of the bow itself. (The sloop carries only one head sail, properly called a foresail though nowadays usually called a jib.) Correctly speaking, a jib is set on the topmast forestay.
The term is English in origin and refers to a specific type of vessel, namely, "a small, decked ship with one mast and bowsprit, traditionally with a gaff mainsail, though not invariably so. The foot of the mainsail would normally be laced to a boom and the head to a gaff above which a gaff topsail would be set in suitable conditions. There would also be a foresail and jib and possibly a flying jib set above the jib.