Monolateral

Monolateral is an adjective describing something that involves or affects only one side or one component. The term derives from the Latin roots mono- “one” and lateralis “side.” It is closely related to unilateral, but monolateral is often found in more technical or descriptive contexts and can emphasize the one-sided nature of a condition, process, or structure. In many everyday situations, unilateral is the more common term, but monolateral appears in specialized literature and in some languages.

In medicine and anatomy, monolateral describes findings limited to one side of the body or a single organ. Examples include monolateral swelling, monolateral weakness, or monolateral organ involvement observed in imaging or during examination. In radiology and pathology, a monolateral lesion refers to a lesion confined to one side of an organ. In dentistry and orthopedics, the term can appear in descriptions of devices or pathology localized to one side, such as monolateral implants or supports, though unilateral terminology is frequently used as well.

In international relations and policy, monolateral measures are actions taken by one state or actor without the agreement or cooperation of others. However, unilateral is the more commonly used term in English for such actions, and monolateral may be encountered in more formal or juristic writing.

Monolateral contrasts with bilateral (two sides) and multilateral (involving multiple sides or parties). It is generally used when the emphasis is on one-sidedness rather than on the number of involved entities.