Doodle wiki:
e first appeared in the early seventeenth century to mean a fool or simpleton, and is thought to derive from the Low German "dudeltopf", meaning "fool" or "simpleton". This in turn resulted in the early eighteenth century verb "to doodle", meaning "to swindle or to make a fool of". The most common modern meaning, an aimless drawing while a person's attention is otherwise occupied, emerged in the 1930s either from this meaning or from the verb "to dawdle", which since the seventeenth century has had the meaning of wasting time or being lazy.
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