c.1300, "hard to manage, reckless, violent," from O.Fr. estourdi "violent," originally "dazed," pp. of estourdir "to daze," from V.L. *exturdire, which is presumed to be from L. intensive prefix ex + turdus "thrush." Perhaps the notion is of thrushes eating leftover grapes at wineries and acting drunk (It. tordo "thrush" also means "simpleton," and Fr. has the expression soûl comme une grive "drunk as a thrush"). OED, however, regards all this as "open to grave objection." Sense of "solidly built, strong and hardy" first recorded late 14c.