The definition of utmost is something that is most important, most extreme or greatest.(adjective)
The need for food when you are starving is an example of something that would be described as being of the utmost importance.
See utmost in Webster's New World College Dictionary
Origin: ME utemest < OE utemest, ytemest, double superl. of ut, out
See utmost in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English ūtmest
Origin: : ūt, out; see ud- in Indo-European roots
Origin: + -mest, -most.
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