A foreigner or resident alien in medieval France; specifically, someone not born in the kingdom (historical/legal term).
From Old French 'aubain,' related to 'auban' and 'aubaine,' ultimately from Latin 'albanus' (relating to Alba or foreign). In medieval French law, an 'aubain' had specific legal restrictions and their property could escheat to the crown upon death.
In medieval France, being an aubain meant you had serious legal disadvantages—basically, you were a second-class resident and the king could take your stuff when you died, which was called 'droit d'aubaine.' It's a sobering reminder that citizenship and property rights are surprisingly recent inventions.
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