Enormity is defined as the huge size or scale of something, or is defined as something that is defined as extremely important.(noun)
When you are overwhelmed by the extreme importance of the decision of whether to get married or not, this is an example of a time when you are overwhelmed by the enormity of the decision.
See enormity in Webster's New World College Dictionary
noun pl. enormities
Origin: Fr enormité < L enormitas < enormis, irregular, immoderate, immense < e-, out + norma, rule: see norm
See enormity in American Heritage Dictionary 4
noun pl. e·nor·mi·ties
Origin: French énormité
Origin: , from Old French
Origin: , from Latin ēnormitās
Origin: , from ēnormis, unusual, enormous; see enormous. Usage Note: Enormity is frequently used to refer simply to the property of being great in size or extent, but many would prefer that enormousness (or a synonym such as immensity) be used for this general sense and that enormity be limited to situations that demand a negative moral judgment, as in Not until the war ended and journalists were able to enter Cambodia did the world really become aware of the enormity of Pol Pot's oppression. Fifty-nine percent of the Usage Panel rejects the use of enormity as a synonym for immensity in the sentence At that point the engineers sat down to design an entirely new viaduct, apparently undaunted by the enormity of their task. This distinction between enormity and enormousness has not always existed historically, but nowadays many observe it. Writers who ignore the distinction, as in the enormity of the President's election victory or the enormity of her inheritance, may find that their words have cast unintended aspersions or evoked unexpected laughter.
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