Entry 1 sense Webster, 1913 Ringmaster /rĭng'-măsˌ-tẽr/ · Ring·mas·ter · IPA /rˈɪŋmˌæstər/ 01 n. One in charge of the performances (as of horses) within the ring in a circus. 1. One in charge of the performances (as of horses) within the ring in a circus.