In modern English enormity means both ‘huge size’ (the enormity of the task) and ‘great wickedness’ or ‘a wicked act’ (How could such an apparently innocuous person be guilty of these enormities?). The latter two senses are the older established ones (though probably less common now), and traditionalists think that the meaning ‘huge size’ should be rendered either by enormousness or another word such as vastness or immensity