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the whole face
(wearing an expression) all over one's face
満面まんめんの笑みえみを浮かべるうかべる。
To have a broad smile on one's face.
満面まんめんの笑顔えがおで迎えむかえた。
She greeted me with a beaming smile.
彼かれは満面まんめんの笑みえみだった。
He had a big smile on his face.