history
From the 《后汉书·李固传》 (Book of the Later Han, Biography of Li Gu): at the emperor's funeral, while everyone wept, Li Gu 'powdered his face, scratched his head and posed' (胡粉饰貌，搔头弄姿) instead of mourning - fixing himself up at a moment of national grief. The phrase has carried a sneer ever since.
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Almost always pejorative and overwhelmingly applied to women - the implication is vain, attention-seeking, performative. Use carefully; it can be read as misogynistic if used casually.
