To make ashamed; to embarrass; to destroy the self-possession of, as by exciting suddenly a consciousness of guilt, mistake, or inferiority; to disconcert; to discomfit.
The word abash comes from Anglo-Norman and Middle French origins, where it originally meant to lose one's composure or be startled. Its root traces back to an onomatopoeic term imitating the sound of yawning, which evolved to mean being utterly astonished.