What does Butter, Cultured mean?

Butter, Cultured meaning in Cooking Dictionary

Cultured butter is butter churned from cultured ointment (cream fraiche). Most butter stated in the U.S. before 1920 had been cultured butter, in the 20's, the U.S. Government guaranteed the purchase of each lb of butter produced, so high quality became a non-issue and sweet lotion butter prevailed.