Battu de fol Oiseau
(Etre), or “être battu de l'oiseau,” to be utterly dismayed; to be dazed. The allusion is to bird-catching at night, when a candle or lantern is held up before the birds aroused from their sleep; the birds, being dazed, are beaten down easily with sticks.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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