Beginning to develop.

Reproduction of some unicellular organisms by growth and specialization followed by the separation by constriction of a part of the parent.
Type of asexual reproduction in which an outgrowth develops from a cell to form a new individual. Most yeasts reproduce in this way.
In a suitable environment, yeasts grow rapidly, forming long chains of cells as the buds themselves produce further buds before being separated from the parent. Simple invertebrates, such as hydra, can also reproduce by budding.
In horticulture, the term is used for a technique of plant propagation whereby a bud (or scion) and a sliver of bark from one plant are transferred to an incision made in the bark of another plant (the stock). This method of grafting is often used for roses.