Definition: an untrustworthy person, especially somebody who influences others
Example: My mother always warned me to stay away from little Nicky Smith. ‘He’s a real bad apple’, she would say.
There have been a number of varied uses for the phrase bad apple in the printed word going back to the 1300s.
In Chaucer’s The Canterbury Tales, readers are advised that a ‘rotten appulle’ should be thrown away before it spoils others. Benjamin Franklin (the guy who flew kites during thunderstorms) warned his readers ‘The rotten apple spoils his companion‘.
And so on. And so forth. There is a recurring theme showing.
A single rotten apple can contaminate all the others stored with it. The science bit? The spoiling one gives off ethylene which speeds up the ripening process in its companions.
So, just like that rotting fruit, a single malicious or dishonest person can affect everyone about them.
Iddy looks a bit like an apple himself. A particularly sour one.