[mod.u.late] vb -lat.ed ; -lat.ing [L modulatus, pp. of modulari to play, sing, fr. modulus small measure, rhythm, dim. of modus measure--more at mete] vt (1615) 1: to tune to a key or pitch
2: to adjust to or keep in proper measure or proportion: temper
3: to vary the amplitude, frequency, or phase of (a carrier wave or a light wave) for the transmission of intelligence (as by radio); also: to vary the velocity of electrons in an electron beam ~ vi 1: to play or sing with modulation
2: to pass from one musical key into another by means of intermediary chords or notes that have some relation to both keys
3: to pass gradually from one state to another -- mod.u.la.tor n -- mod.u.la.to.ry adj