When you learn a new word and then suddenly start seeing it everywhere you go, it’s called the Baader-Meinhof phenomenon (aka frequency illusion). It happens because your brain is good at seeing patterns, confirming its own biases, and obsessing over interesting information. You’re also learning new words all the time, but you don’t always encounter them again right away– so when you do, your brain continues to accept it as a meaningful pattern even though it’s just a random coincidence. Source Source 2 Source 3