While this saying does not refer to an actual bug, the idea comes from the buzzing sounds they make. That is definitely a good thing, as no one would want actual bugs put in their ear. (Photo used with permission of Andrew Stern)
Have you ever heard a person mentioning “putting a bug” in someone’s ear? If so, they were probably not talking about putting a literal bug in an ear. Instead, this phrase means giving a hint about something, trying to give someone information without actually telling them.
For example: “I’ve been putting a bug in his ear for months about what I wanted for my birthday, but he got me something completely different,” or “since the project is worth a big part of our grade, she had to put a bug in her partner’s ear about the deadline.”
While it is unclear exactly when and how this saying came about, people have estimated that usage started in the 14th century and it has French origins. The analogy is supposedly relating the buzzing of insects to people giving reminders or suggestions to each other.
People may notice that there is a similar British idiom that is “to put a flea in someone’s ear.” It comes from the same 14th century French origins, but has a different purpose — when it was first used in English it meant giving someone spiritual emotion, but now people use the saying when reprimanding someone or sending them away with a warning.