= monotonic, adj.

(Of a sound, utterance, etc.) continuing on or repeating the same note; having little or no variation in tone or pitch; (of a musical instrument)…

Of a sound or utterance: continuing on or repeating the same note; having little or no variation in tone, pitch, or cadence. Also, of a musical…

Of, relating to, or uttered in a monotone; (of an instrument or a line of music) limited or confined to one tone or pitch.