A feeling of being at ease, feeling relaxed and untroubled.(noun)
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Use "easiness" in a sentence
"For Eloquence is scarcely the Lot of one or two Men; nay, if we may believe Marc Antony, of none: But that which Candidus calls easiness of Speaking, is the Talent of many, and chiefly of the most assur'd."
"The problem, I think, lies in the deceptive "easiness" of thyroid treatment."
"What kind of easiness that is, they may best judge that understand how easy men are that can murder people to prevent danger."