dys·rhyth·mia I. \də̇sˈrithmēə sometimes -th-\noun (-s) Etymology: New Latin, from dys- + Latin rhythmus rhythm + New Latin -ia — more at rhythm : abnormal rhythm; specifically: disordered rhythm in the brain waves as disclosed by an electroencephalogram • dys·rhyth·mic\(ˈ)dis|rithmik, dəsˈr- sometimes -th-\adjective II. noun : jet lag herein