Tech & Science dictionary
Baader-Meinhof phenomenon
Baader-Meinhof effect [ bey-der mahyn-hawf fi-nom-uh-non ]
What is Baader-Meinhof phenomenon?
The Baader-Meinhof phenomenon (also known as the Baader-Meinhof effect or the frequency illusion) is a name for the experience of learning of or encountering something for the first time and then very soon after encountering it again, often in multiple places. The sensation is thought to result from having an increased awareness of the thing after the first encounter.
For example, immediately after learning a new word, many people have the experience of immediately encountering it again, sometimes in several different pieces of writing over a short period of time, making it seem like a strange coincidence.
Where does Baader-Meinhof phenomenon come from?

The Baader-Meinhof phenomenon is named for the Baader-Meinhof Gang, a 1970s German terrorist group. The name of the phenomenon is thought to have been coined by Terry Mullen, who explained his experience with it in a 1994 letter to a Minnesota newspaper. Mullen said he started using the name due to the experience of having discussed the Baader-Meinhof Gang and then encountering a mention of the group in the newspaper the next day, despite the fact that the group hadn’t been newsworthy for many years. Mullen applied the term to the experience of encountering a word or idea in print within 24 hours after first learning it. Today, the term is typically used more broadly.
The word phenomenon is used in the names of other psychological experiences.
Scientifically, the phenomenon is thought to be due to a type of cognitive bias in which the brain prioritizes new information and focuses more attention on it. This can result in the sensation that something has increased in frequency when it actually hasn’t (hence the synonymous term frequency illusion).
Examples of Baader-Meinhof phenomenon
Who uses Baader-Meinhof phenomenon?
The terms Baader-Meinhof phenomenon and frequency illusion are names for something that a lot of people experience. A common joke is that learning the term Baader-Meinhof phenomenon is likely to result in experiencing the Baader-Meinhof phenomenon. If you’re on this page because you’re learning the term for the first time, expect to encounter it again soon!
Once you learn about the Baader–Meinhof phenomenon, you start seeing it everywhere.
— Allen Baranov 🌻 (@abaranov)
I've learned about awkwafina's existence a couple days ago, and now everyone talks about her all of a sudden. classic case of baader-meinhof phenomenon
— Big Gleb (@GlebMelnikov8)
One of my favorite things about finally having watched The Matrix for the first time is that the frequency illusion/Baader-Meinhof phenomenon is kicking in so I feel very smart and like I am seeing glitches in the matrix
— Jax Romana, 100% Bi Maidenless Behavior🌹🏳️🌈 (@RuffleJax)
Note
This is not meant to be a formal definition of Baader-Meinhof phenomenon like most terms we define on Dictionary.com, but is rather an informal word summary that hopefully touches upon the key aspects of the meaning and usage of Baader-Meinhof phenomenon that will help our users expand their word mastery.