What is the X in X-mas?
mid-14c., "a plum," also "a dried plum" (c.1200 in place name Prunhill), from Old French pronne "plum" (13c.), from Vulgar Latin *pruna, fem. singular formed from Latin pruna, neuter plural of prunum "a plum," by dissimilation from Greek proumnon, from a language of Asia Minor. Slang meaning "disagreeable or disliked person" is from 1895. Prune juice is from 1807.
early 15c., prouyne, from Old French proignier "cut back (vines), prune" (Modern French provigner), of unknown origin. Perhaps [Watkins] from Gallo-Romance *pro-retundiare "cut in a rounded shape in front," from pro- "forth" (see pro-) + *retundiare "round off," from Latin rotundus (see round (adj.)). Klein suggests the Old French word is from provain "layer of a vine," from Latin propago (cf. prop (n.1)).
Or the Middle English word might be identical with the falconry term proinen, proynen "trim the feather with the beak" (late 14c.), source of preen [Barnhart]. Related: Pruned; pruning. Pruning hook is from 1610s; pruning knife from 1580s.
To accelerate faster than another car in a race (1940s+ Hot rodders)
in horticulture, the removal or reduction of parts of a plant, tree, or vine that are not requisite to growth or production, are no longer visually pleasing, or are injurious to the health or development of the plant. Pruning is common practice in orchard and vineyard management for the improvement of flowering and fruiting. In home gardening (e.g., rose culture), pruning enhances plant shape and flowering potential; new growth emerges from the bud or buds immediately below the pruning cut. The once-common practice of cutting off a branch so that its base is flush with the limb is now recognized as inadvisable. Instead, the pruning cut should be made just above the collar, or swelling-essentially a protective callus-that surrounds the base of the branch. Ragged bark at the edge of the wound should be carefully trimmed. The application of pruning paint, or dressing, also a once-common practice, is unnecessary, but thin coasts may be applied for cosmetic reasons. Incorrect pruning can cause flower and fruit loss and leave the plant weak and vulnerable to disease or insect damage