(1):

(a.) Deviating from that which is customary; novel; strange; unusual.

(2):

(a.) Haughty and contemptuous or brutal in behavior or language; overbearing; domineering; grossly rude or disrespectful; saucy; as, an insolent master; an insolent servant.

(3):

(a.) Proceeding from or characterized by insolence; insulting; as, insolent words or behavior.