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intentionally; deliberately; designedly; on purpose
especially; particularly
彼はことさら難しい言葉を使って話す癖がある。
He has a habit of deliberately using difficult words when he speaks.
ことさら問題を大きくする必要はないだろう。
There is no need to deliberately make the problem bigger.
彼女はことさら平静を装って会議室を出た。
She left the conference room deliberately putting on a calm front.