From Latin volitio, from velle, to wish.
volitional (comparative more volitional, superlative most volitional)
- done by conscious, personal choice; not based on external principles.
- 1922, James Joyce Ulysses
- A man of genius makes no mistakes. His errors are volitional and are the portals to discovery.
- done intentionally, not by accident
- Alcoholism : the volitional disease. 
- (rare) pertaining to volition