Definitions of bud:

• noun:   a partially opened flower
• noun:   a swelling on a plant stem consisting of overlapping immature leaves or petals
• verb:   start to grow or develop

  Example: "A budding friendship"

• verb:   develop buds

  Example: "The hibiscus is budding!"

• name:  A male given name (rare: 1 in 20000 males; popularity rank in the U.S.: #951)
• name:  A surname (very rare: popularity rank in the U.S.: #74547)