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approximately; about
promise; appointment; engagement
shortening; reduction; simplification
contraction (in phonetics)
駅から家までは約三十分で到着できます。
We can arrive at the station in about thirty minutes.
今回の参加者は約百名だった。
There were about one hundred participants this time.
全部で約一万円かかると思う。
I think it will cost about 10,000 yen in total.