breakopen

Breakopen is a verb phrase that denotes opening something by breaking or forcing entry. It is typically used when the object being opened resists ordinary opening methods, or when the act of opening is accompanied by some damage to the object’s seal, shell, or structure. The phrase can be used transitively, as in break open the lid, or intransitively in a figurative sense, as the door finally breaks open after a struggle. The form is commonly hyphenated as break-open; unhyphenated breakopen is less common but encountered in some texts.

In firearms, break-open or break-action refers to a specific mechanism in which the barrel or barrels hinge away from the receiver on a pivot to expose the breech. The action is opened by breaking the gun along a horizontal or vertical line and is typically released by a latch or lever. Break-open firearms are commonly single-shot or double-barreled shotguns and rifles; they are valued for mechanical simplicity, reliable sealing of the breech, and straightforward cleaning. Limitations include slower cycling compared to bolt-action or repeating designs and, in many configurations, limited ammunition capacity.

Outside firearms, break-open is used to describe packets, shells, or seals designed to be opened by breaking, such as certain novelty containers or emergency rations. In general usage today, the term emphasizes the forceful or dramatic nature of opening, rather than a smooth or incremental motion. See also break-action, break-in, and related terms.