the.com/clinch

means To settle or secure something decisively, or to grip and hold someone or something tightly.

from A variant of "clench," both descending from Old English "beclencan," meaning to hold fast or make cling — a cousin of "cling" itself. The senses split over time: "clench" kept the fist, while "clinch" drifted toward fastening a nail by bending its tip and, by extension, nailing down a deal. The boxing "clinch" — two fighters locked tight — arrived as a natural fit for a word already about gripping and not letting go.