(of words or language) having little or no meaning; making little or no sense: A baby's babbling is appealingly nonsensical.
(of behavior, conduct, actions, etc.) foolish, senseless, fatuous, or absurd: His nonsensical behavior was unusual for such a serious person.
objectionable, impudent, insubordinate: I refuse to listen to that nonsensical gossip.
of trifling importance or of little or no use: I've had more than enough of your nonsensical advice!
nonsensicality, nonsensicalness, noun