Blocked or stopped up; also meaning actively promoted or advertised, or hit with a bullet (slang).
From Dutch 'plugge' (stopper), which may derive from German 'Pflug' (plow) or be related to Flemish origins; adopted into English in the 1600s.
Plugged is a word with multiple slang meanings that emerged at different times—a hole can be plugged (stopped), a product can be plugged (promoted), and someone can be plugged (shot)—each meaning using the core idea of insertion.
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