Out-rigger is a nautical term used to describe a component of boats and ships that is used to keep vessels stable in the water. There are numerous synonyms that can be used to describe the out-rigger, including support, stay, prop, brace, strut, and stanchion. Additionally, the term can be used interchangeably with words like appendage, extension, and add-on. These synonyms can all be used to describe the same concept, which is a sturdy component incorporated into a vessel's design to provide stability in rough water conditions. Regardless of the specific word used, the function of the out-rigger remains constant: to keep boats and ships from capsizing or rolling over in rough seas.