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unsatisfying; disappointing; abrupt; not enough; too quick; too short; over too soon
結末が呆気ないほどあっさりしていた。
The ending was disappointingly simple.
優勝決定戦は呆気なかったと観客が嘆いた。
The spectators lamented that the championship match was over too quickly.
彼の演説は呆気なくないが少し短かった。
His speech was not unsatisfying, but it was a bit short.