n.
  - a loud rumbling or crashing noise heard after a lightning flash due to the expansion of rapidly heated air.
 - a resounding loud, deep noise.
 
v.
   - 
(it thunders, it is thundering, etc.)
 thunder sounds.
 - move heavily and forcefully.
 - speak loudly, angrily, and forcefully, especially to protest:
 he thundered against the evils of the age.
 
 
  Derivative
  
    - thunderer n.
  - thundery adj.
 
   
  Etymology
  OE thunor (n.), thunrian (v.), of Gmc origin.