Appropriate or suitable; fitting for the situation or purpose.
この場面で彼の発言は適切だった。
His remark was appropriate in that situation.
適切な時に適切な対応を取ることが重要だ。
It's important to take appropriate action at the appropriate time.
その例は説明に対して適切とは言えない。
That example cannot be said to be appropriate for the explanation.