Main entry: digressive, discursive, rambling, excursive
Definition: (of e.g. speech and writing) tending to depart from the main point or cover a wide range of subjects
Usage: amusingly digressive with satirical thrusts at women's fashions among other things; a rambling discursive book; his excursive remarks; a rambling speech about this and that
Main entry: digressive, tangential
Definition: of superficial relevance if any
Usage: a digressive allusion to the day of the week; a tangential remark