Can a star only be bigger in height and width than the sun or can a star be heavier than the sun or is that impossible?

Question: Can a star only be bigger in height and width than the sun or can a star be heavier than the sun or is that impossible?
- Keywords:
  space,
  star,
  universe
Asked by qureshir to Nick on 10 Mar 2014.
- Nick Wright answered on 10 Mar 2014:
  
  A star can be bigger and heavier than the Sun, in fact the biggest stars are often the heaviest (though not always!).

Question: Can a star only be bigger in height and width than the sun or can a star be heavier than the sun or is that impossible?