Definition of fights:
(v) :
(transitive) To engage in combat with; to oppose physically, to contest with.
(v) :
(intransitive) To contend in physical conflict, either singly or in war, battle etc.
(n) :
A physical confrontation or combat between two or more people or groups.
(v) :
(transitive) To conduct or engage in (battle, warfare, a cause, etc.).
(n) :
A conflict, possibly nonphysical, with opposing ideas or forces; strife.
(n) :
An occasion of fighting.