di·va·gate /ˈdaɪvəˌget, ˈdɪ-/
  (v.)流浪;入岐途;離題
  divagate
       v : lose clarity or turn aside especially from the main subject
           of attention or course of argument in writing, thinking,
           or speaking; "She always digresses when telling a story";
           "her mind wanders"; "Don't digress when you give a
           lecture" [syn: digress, stray, wander]