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plain; frank; candid; open; direct; straightforward; unabashed; blatant; flagrant
「白地」 has other readings with different meanings.
白地な物言いで相手の欠点を指摘するのは勇気がいる。
It takes courage to point out someone's faults with frank speech.
白地に意見を述べたことで会議の雰囲気が変わった。
The atmosphere of the meeting changed after they spoke their mind frankly.
彼女は白地な性格で周囲からの信頼が厚い人物だ。
She is a person of frank character who is highly trusted by those around her.