Baader–Meinhof Phenomenon

What is the Baader-Meinhof phenomenon?

The Baader-Meinhof phenomenon, also called the Baader-Meinhof effect or frequency illusion, is the experience of suddenly noticing a word, idea, or object everywhere after you first become aware of it. Learn about a new type of bird, then spot it all over the neighborhood: that is the familiar experience the term describes.

Arnold Zwicky connects it to selective attention and confirmation bias. Newly noticed examples stand out; the times you do not encounter the thing receive less attention. That explains how something can seem more common without becoming more common. Sometimes its actual frequency has changed too.

Source: Zwicky’s account of the frequency illusion and its terminology.