Japan's Cultural Code Words, 「知らん顔」の項の英語タイトルは "Keeping a Straight Face" となっていました。その中の一部を抜粋します。
From day-to-day personal relations to business and political matters, it is still important and frequently vital for the Japanese to put on a shirankao to protect themselves from their custom of not clearly verbalizing their opinions, goals, or objections, and from the behind-the-scenes activities that characterize their relationships.
と言うような具合で、知らん顔をする事は日本人の特技、特性だと著者は指摘しています。確かに、知らん顔をする事は、誰にでも一度や二度は経験があると思いますが、それは日本人だけの特技ではないと思います。日本人による真珠湾攻撃があることは米国の首脳（多分大統領も）は知っていたのですが、 「知らん顔」をしましたし、ベトナム戦争や湾岸戦争での非人道的な行為も 「知らん顔」をした米国人は少なくないと思います。
説明文にはどこにも "straight face" は使われていませんが、 「知らん顔」を次ぎの様に説明しています。
One facet of this traditional Japanese behavior that continues to have an impact on outsiders, particularly on Westerners, is the facial expression known as shirankao (she-rahn-kow), which literally translated as "an I-don't-know face" or "a face that doesn't know." By extension, shirankao also refers to a face that shows nothing--a face that does not reveal and individual's feelings of intentions--in other words, a "poker face."
さて、 "straight face" にも「知らん顔」の意味があるか辞書で確認します。
・Collins Dictionary: a serious facial expression, esp one that conceals the impulse to laugh: I won't get married if you say not to,' I hope she joked through a straight face.
・Merriam-Webster's Online Dictionary: a face giving no evidence of emotion and especially of merriment: lied with a straight face
・Cambridge English Dictionary: a serious expression on your face that you use when you do not want someone to know that you think something is funny: Brian looked ridiculous in leather trousers, and I was desperately trying to keep a straight face.
・Vocabulary.com: a serious facial expression giving no evidence of interest or amusement: Most times the straight faces of the military men and women in front of me do not budge.”
"poker face" とほとんど同じですね。
From day-to-day personal relations to business and political matters, it is still important and frequently vital for the Japanese to put on a shirankao to protect themselves from their custom of not clearly verbalizing their opinions, goals, or objections, and from the behind-the-scenes activities that characterize their relationships.
と言うような具合で、知らん顔をする事は日本人の特技、特性だと著者は指摘しています。確かに、知らん顔をする事は、誰にでも一度や二度は経験があると思いますが、それは日本人だけの特技ではないと思います。日本人による真珠湾攻撃があることは米国の首脳（多分大統領も）は知っていたのですが、 「知らん顔」をしましたし、ベトナム戦争や湾岸戦争での非人道的な行為も 「知らん顔」をした米国人は少なくないと思います。
説明文にはどこにも "straight face" は使われていませんが、 「知らん顔」を次ぎの様に説明しています。
One facet of this traditional Japanese behavior that continues to have an impact on outsiders, particularly on Westerners, is the facial expression known as shirankao (she-rahn-kow), which literally translated as "an I-don't-know face" or "a face that doesn't know." By extension, shirankao also refers to a face that shows nothing--a face that does not reveal and individual's feelings of intentions--in other words, a "poker face."
さて、 "straight face" にも「知らん顔」の意味があるか辞書で確認します。
・Collins Dictionary: a serious facial expression, esp one that conceals the impulse to laugh: I won't get married if you say not to,' I hope she joked through a straight face.
・Merriam-Webster's Online Dictionary: a face giving no evidence of emotion and especially of merriment: lied with a straight face
・Cambridge English Dictionary: a serious expression on your face that you use when you do not want someone to know that you think something is funny: Brian looked ridiculous in leather trousers, and I was desperately trying to keep a straight face.
・Vocabulary.com: a serious facial expression giving no evidence of interest or amusement: Most times the straight faces of the military men and women in front of me do not budge.”
"poker face" とほとんど同じですね。
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