Outer Trench Swell is a term used in oceanography for describing the swell patterns of remote sea areas. It refers to the waves that form beyond the deep-sea trenches in the open ocean. In scientific literature, this term is sometimes referred to as "trench swell," "outer swell," or "open ocean swell." The swell is known to travel long distances and has a significant impact on the weather and climate patterns of coastal regions. Other expressions that can be used as synonyms for outer trench swell are "open sea waves," "oceanic swells," "remote swells," and "deep-ocean waves." These oceanic swells are crucial for understanding ocean dynamics and serve as important indicators of global weather patterns.