What is Sheldon's catchphrase?

Sheldon Cooper’s catchphrase is “Bazinga!” He typically says it after playing a prank, making a joke, or tricking someone, often as a signal that his remark was meant to be humorous.

The word became one of the defining features of Sheldon’s character on The Big Bang Theory. Sheldon is highly intelligent but socially unusual, and “Bazinga!” reflects his preference for jokes that are carefully controlled rather than spontaneous. The phrase often appears after he has engineered a situation that leaves another character confused or embarrassed.

“Bazinga!” is associated specifically with Sheldon, although other characters occasionally repeat it or use it sarcastically. It is not a scientific term, a reference to a particular equation, or a general catchphrase shared by the show’s main group. The spelling with a final exclamation mark is the familiar version used in the series.

The phrase became popular beyond the show. In 2012, Brazilian scientists named an orchid bee Euglossa bazinga, honoring Sheldon’s catchphrase and noting that the bee had previously fooled researchers because it resembled another species.