Prune2  v. (-ning) 1 a (often foll. By down) trim (a bush etc.) By cutting away dead or overgrown branches etc. B (usu. Foll. By off, away) lop (branches etc.) Thus. 2 reduce (costs etc.) (prune expenses). 3 a (often foll. By of) clear or remove superfluities from. B remove (superfluities). [french prooignier from romanic: related to *round]