What is the deepest point in the Gulf of Mexico called?

The deepest point in the Gulf of Mexico is called the Sigsbee Deep.

Sigsbee Deep is a roughly triangular deep basin in the southwestern part of the Gulf of Mexico. It lies far offshore, with its closest point to the United States coast roughly 200 miles southeast of Brownsville, Texas. The basin includes the broad, flat Sigsbee Abyssal Plain.

The name honors Charles Dwight Sigsbee, a U.S. Navy officer and oceanographic surveyor whose work helped map the Gulf's seafloor. His surveys, conducted aboard the vessel George S. Blake in the late nineteenth century, contributed to the first realistic bathymetric map of a major ocean basin.

Depth figures vary because of differences in surveys and definitions, with estimates generally ranging from about 3,750 to 4,000 meters. “Sigsbee Deep” is also sometimes used alongside “Mexico Basin,” which explains occasional variation in maps and technical references. The Puerto Rico Trench and Mariana Trench are elsewhere.