- Upbeat (mus) - That part of a foot where the ictus is put, or which is
distinguished from the rest (known as the thesis) of the foot by a
greater stress of voice. - That elevation of voice now called metrical accentuation, or
the rhythmic accent. - The elevation of the hand, or that part of the bar at which
it is raised, in beating time; the weak or unaccented part of the bar;
-- opposed to thesis.