Singletree is an old-fashioned term used to describe a wooden bar with a single or double tree at the end that is used to connect a horse or mule to a plow or cart. This tool has been replaced by modern equipment, but there are still many synonyms for singletree in use today, such as: yoke, harness, teamster, plow line, horse fittings, bridle, traces, and more. These words often refer to the same type of equipment used in different regions or contexts. Although the use of singletrees is not as common as it once was, these synonyms are still useful for those interested in traditional farming or historic methods of transportation.