The state or quality of being unskillful, of lacking skill (noun)
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Use "unskillfulness" in a sentence
"It is true that in a Commonwealth, where by the negligence or unskillfulness of governors and teachers false doctrines are by time generally received, the contrary truths may be generally offensive: yet the most sudden and rough bustling in of a new truth that can be does never break the peace, but only sometimes awake the war."
"Which makes the unskillfulness of some alchemists of the reformed school all the more remarkable — who have conceived that by the equable warmth of lamps and the like, burning uniformly, they can attain their end."
"For to use the knife, unless in the extremest necessity, is neither good surgery nor wise policy, but in both cases mere unskillfulness; and in the latter, unjust as well as unfeeling."