quix·ot·ic 
(kwĭk-sŏtĭk) also quix·ot·i·cal (-ĭ-kəl)
(kwĭk-sŏtĭk) also quix·ot·i·cal (-ĭ-kəl)adj.
1. Caught up in the romance of noble deeds and the pursuit of unreachable goals; idealistic without regard to practicality.
2. Capricious; impulsive: "At worst his scruples must have been quixotic, not malicious" (Louis Auchincloss).
[From English Quixote, a visionary, after Don Quixote, hero of a romance by Miguel de Cervantes.]
quix·oti·cal·ly adv.
quixo·tism (kwĭksə-tĭz′əm) n.