露 has two common pronunciations: lù (formal/written: 露水 dew, 暴露 expose) and lòu (colloquial: 露馅 give away a secret, 露出马脚 show one's true colors). Both mean 'to reveal.'
usage
露出马脚 (lòu chū mǎjiǎo, 'reveal a horse's foot') means to accidentally expose a deception — like a disguise where the horse's hooves peek out.
