ob·scu·ri·ty 
(ŏb-skyrĭ-tē, əb-)
(ŏb-skyrĭ-tē, əb-)n. pl. ob·scu·ri·ties
1. Deficiency or absence of light; darkness.
2.
a. The quality or condition of being unknown: "Even utter obscurity need not be an obstacle to [political] success" (New Republic).
b. One that is unknown.
3.
a. The quality or condition of being imperfectly known or difficult to understand: "writings meant to be understood ... by all, composed without deliberate obscurity or hidden motives" (National Review).
b. An instance of being imperfectly known or difficult to understand.