To turn aside from the main subject in writing or speaking.
turn aside esp. from the main subject of attention or course of argument in writing or speaking; "She always digresses when telling a story"
wander from a direct or straight course
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"
lose clarity or turn aside especially from the main subject of attention or course of argument in writing, thinking, or speaking