Not faithful or true to a person, group, or cause; breaking trust or betraying someone's confidence.
From Old French 'desloial,' combining the prefix 'des-' (opposite of) with 'loyal' (faithful). The 'loyal' part comes from Latin 'legalis' through Old French, originally meaning 'legal' or 'according to law.'
The word 'disloyal' is fascinating because it connects loyalty to legality—in medieval times, being loyal meant following the legal rules of your lord or king! Your loyalty was quite literally a legal obligation, not just an emotional one.
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