in·con·gru·ous 
(ĭn-kŏnggr-əs)
(ĭn-kŏnggr-əs)adj.
1. Lacking in harmony; incompatible: a joke that was incongruous with polite conversation.
2. Not in agreement, as with principles; inconsistent: a plan incongruous with reason.
3. Not in keeping with what is correct, proper, or logical; inappropriate: incongruous behavior.
[From Latin incongruus : in-, not; see IN-1 + congruus, congruous; see CONGRUOUS.]
in·congru·ous·ly adv.
in·congru·ous·ness n.