Pollarding refers to the practice of cutting back a tree's branches to a specific point repeatedly to promote new growth. Antonyms for pollarding are words that imply the opposite of this process. One such antonym is "pruning," which often involves cutting back branches on a tree or plant to shape or maintain its size. Another antonym for pollarding is "thickening," which is the process of allowing tree branches to grow and expand without being cut back. Lastly, "enlarging" is another antonym for pollarding, which implies the act of allowing tree branches to grow freely, without being hindered or cut back.