(1):

(a.) Being in the greatest or highest degree, quantity, number, or the like; greatest; as, the utmost assiduity; the utmost harmony; the utmost misery or happiness.

(2):

(n.) The most that can be; the farthest limit; the greatest power, degree, or effort; as, he has done his utmost; try your utmost.

(3):

(a.) Situated at the farthest point or extremity; farthest out; most distant; extreme; as, the utmost limits of the land; the utmost extent of human knowledge.