beard [OE] Beard, which is related to Latin barba ‘beard’, is of common Germanic stock but otherwise of unknown origin. As a verb [LME] to beard could mean ‘to confront someone, be insolent, defy’ (compare modern ‘in your face’), hence to beard the lion in his den or lair [M18th], ‘to confront or challenge someone on their own ground’, based on a story in the biblical First Book of Samuel 17:35, where David kills a lion that has stolen a lamb, grabbing it by what is now translated as its jaw, but in some earlier English translations was beard. To run in someone’s beard was to defy him, and by the 16th century you could simply ‘beard someone’. Clearly this stopped being fearsome enough, and lions were introduced in the 18th century.