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(matter) for congratulations; worthy of celebration; happy (occasion, ending, etc.); joyous; auspicious
naive; too good-natured; gullible; foolish; simple
結婚は本当におめでたいことですよね。
Marriage is a happy occasion.
彼はおめでたい人で何でも信じる。
He's naive and believes everything.
娘が志望校に合格して、本当におめでたかった。
My daughter got accepted to her school of choice — it was truly a happy occasion.