a man holding the lowest hereditary British title, below a baron but above a knight: a baronet is addressed as “Sir,” and may add “Bart.” to his name, as Sir John Doe, Bart.
this title
Origin:
ME, dim. of baron
See baronet in American Heritage Dictionary 4
noun
A man holding a British hereditary title of honor reserved for commoners, ranking immediately below the barons and above all orders of knighthood except the Garter.
Abbr. Bart. or Bt. Used as the title for such a man.