No. He was Macbeth mac Findlaech, or Macbeth son of Findlaech. The name "Macbeth" appears earlier in the king lists for Moray and may have been a common given name in the royal family. It means "son of life" (beatha is the Gaelic word for life), and may have originated as an affirmation of the bearer's Christianity. In some texts, the name is given as "Maelbeatha," which would translate as "servant of life."
As a humorous footnote, in one of the books I read--published in the 1940s--the author stated that there was no word "beth" in Gaelic, and so this must be a Pictish name, making Macbeth a descendant of the Picts. What a choice example this is of how conflicting histories can arise!
Next: Macbeth's World