In medieval times sturdy meant ‘reckless, violent’ and ‘intractable, obstinate’. The word is a shortening of Old French esturdi ‘stunned, dazed’, and is thought to be based on Latin turdus ‘a thrush’: thrushes were formerly associated with drunkenness, possibly because of eating wine grapes. Interestingly, there is an old French phrase soûl comme une grive, which means ‘drunk as a thrush’.