B meson

noun

: any of a class of short-lived mesons that are thought to be a combination of one bottom antiquark and either an up, down, or strange quark

Note: B mesons are primarily useful for theoretical purposes, such as verifying proposed models that explain the natural laws of the universe.

Since then, independent teams … have been colliding tens of millions of electrons and their antimatter counterparts, positrons, looking for firm evidence of B meson CP violation.—

Peter Weiss, Science News, 3 Mar. 2001

Answering that question has become The Next Big Thing in high-energy physics, and the quest is focusing on a short-lived, formerly obscure particle called the B meson that is produced in particle collisions.—

Curt Suplee, Washington Post, 13 Oct. 1997