pl. n.
 
[
usu. treated as sing.]
  
- the branch of philosophy concerned with the first principles of things, including abstract concepts such as being and knowing.
 - informal abstract theory.
 
 
  Derivative
  
  Etymology
  C16: representing med. L. metaphysica (neut. pl.), based on Gk ta meta ta phusika ‘the things after the Physics’, referring to the sequence of Aristotle's works.