early 15c., prouyne, from O.Fr. proignier "cut back (vines), prune," of unknown origin, perhaps from Gallo-Romance *pro-retundiare "cut in a rounded shape in front," from pro- "forth" + *retundiare "round off," from L. rotundus (see
round). The M.E. word may be via falconry
term proinen "trim the feather with the beak" (late 14c.), Related to preen (q.v.). Related: Pruned; pruning.