A person who fails a test, class, or exam, especially in school.
From 'flunk,' possibly from German 'plumpen' (to fail or tumble), which came into American English in the 1800s. The -er suffix creates an agent noun—someone who performs the action of flunking.
The word 'flunk' arrived in American college slang, probably from German immigrants, and has become such a standard part of school vocabulary that few students realize it's a relatively young word in English.
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