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easily; readily; quickly; flatly (refuse)
lightly (seasoned food, applied make-up, etc.); plainly; simply
彼はあっさりと彼女の誘いを断った。
He flatly refused her invitation.
あっさりした味付けの料理が好きです。
I like lightly seasoned dishes.
難しいと思った問題があっさり解けた。
A problem I thought was difficult was solved easily.