Synonyms for Nonsensical (same or very similar meaning)
WordNet sense 1 (incongruous;inviting ridicule):
absurd, cockeyed, derisory, idiotic, laughable, ludicrous, preposterous, ridiculousWordNet sense 2 (devoid of good sense or judgment):
foolishWordNet sense 3 (having no intelligible meaning):
nonsenseWordNet sense 4 (having no meaning or direction or purpose):
meaningless, nonmeaningfulFrom the ODE community, based on WordNetadd/edit