digression
     n 1: a message that departs from the main subject [syn: {aside},
          {excursus}, {divagation}, {parenthesis}]
     2: a turning aside (of your course or attention or concern); "a
        diversion from the main highway"; "a digression into
        irrelevant details"; "a deflection from his goal" [syn: {diversion},
         {deviation}, {deflection}, {deflexion}, {divagation}]
     3: wandering from the main path of a journey [syn: {excursion}]
Source: WordNet® 2.0