The term "baby boomer" was originally meant to define the generation of people born after World War II, when the United States saw a spike in births. Now, uttering the words "OK, boomer" on social media signals a write-off insult to an older person, generally someone perceived as out of touch with current society, or more aggressively closed-minded.

Boston Globe columnist and noted baby boomer Alex Beam joined Boston Public Radio on Thursday to explain the term.