Mob.opponent' is a `field' but a `type' was expected help please! :)

i get this error Assets/myscripts/Mob.cs(62,57): error CS0118: Mob.opponent' is a field' but a `type' was expected here is my code

 using UnityEngine;
 using System.Collections;
 
 public class Mob : MonoBehaviour 
 {
     public float speed;
     public float range;
 
     public CharacterController controller;
     public Transform player;
     private Fighter opponent;
 
     public AnimationClip run;
     public AnimationClip idle;
     public AnimationClip die;
     public AnimationClip attackClip;
 
     public double impactTime = 0.36;
 
     public int health;
     public int damage;
 
     private bool impacted;
     
     // Use this for initialization
     void Start () 
     {
          opponent = player.GetComponent<Fighter> ();
     }
     
     // Update is called once per frame
     void Update () 
         {
         Debug.Log (health);
             if(!isDead ()) 
                     { 
 
         
                         if(!inRange ())
                              {
                             chase ();
                             }
                         else
                         {
                             animation.Play(attackClip.name);
                         }
 
                     }
                     else 
                     {
             dieMethod(); 
                     }
 
                     }
         
 
 
             void attack()
                 {
                     if(animation[attackClip.name].time>animation[attackClip.name].length*impactTime&&!impacted)
                         {
                             opponent.getHit
                             impacted = true;
                         }
                 }
 
 
             bool inRange()
                 {
                     if(Vector3.Distance(transform.position, player.position)<range)
                     {
                         return true;
                     }
                     else
                     {
                         return false;
                     }
                 }
             
 
 
             public void getHit(int damage)
                 {
                     health = health - damage;
                     if(health<0)
                     {
             health = 0;
                     }
             }
 
             
             void chase()
                 {
                     transform.LookAt(player.position);
                     controller.SimpleMove(transform.forward*speed);
                     animation.Play(run.name);
                 }
 
                 void dieMethod()
                     {
                             animation.Play(die.name);
                             if(animation[die.name].time>animation[die.name].length*0.9)
                                 {
                                 Destroy(gameObject);
                                 }
                     }
 
 
 
 
 
     bool isDead()
                 {
                     if(health <= 0)
                     {
                         return true;    
                     }
                         else 
                         {
                             return false;
                         }
                 }
             void OnMouseOver()
                 {
                 player.GetComponent<Fighter>().opponent = gameObject;
                 }
     
     
 
 
             
 }