ictus /ˈɪktəs/ noun4 •The stress of voice laid upon an accented syllable of a word. Compare arsis. •In conducting, the indication of a musical event, most often the beat of the tempo or the entry of a section of the orchestra. •A sudden attack, blow, stroke, or seizure, as in a sunstroke, the sting of an insect, pulsation of an artery, etc. •The pulse. formsictuses · ictusses