The term "most sharp-cornered" denotes an object or item that has pointed or angled corners. Antonyms for this word include those that describe objects with rounded edges, smooth contours or curves. For example, words like "rounded," "curved," "sleek," and "streamlined" could be used as antonyms. Other antonyms for "most sharp-cornered" include "blunt," "dull," "flat," and "squarish." Such antonyms could be used when referring to the opposite of a sharp and pointy object, such as a blunt or smooth-edged tool, a gentle curve or a soft, rounded line.