See easiness in Webster's New World Roget's A-Z Thesaurus II
noun
The ability to perform without apparent effort:
ease, effortlessness, facileness, facility, readiness. See easyFreedom from constraint, formality, embarrassment, or awkwardness:
casualness, ease, informality, naturalness, poise, spontaneity, unceremoniousness, unrestraint. See restraint, tighten
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