problem in var atemp : String[]

You're mixing Javascript and c#, if you want to split a string based off new line, give it a couple options for different platforms to split on, i.e. \n and \r\n

I assume the variable tWordList is derived from DestrroyOnClick or somewhere down the chain as there isn't a direct reference in the textdisplay1 class.

using UnityEngine; using System.Collections;

 public class textdisplay1 : DestrroyOnClick { 
     public TextAsset asset;
 
     public int searchWord (string a) {
         string[] aTemp = tWordList.text.Split(new string[] { "\r\n", "\n" }, StringSplitOptions.None);
         // display string array items in Unity Console for sanity check.
         if (aTemp != null){
             for (int i = 0; i < aTemp.Length; i++) {
                 Debug.Log("WordList Word: " + aTemp[i]);
             }
         }
         
         return 1;
     }
 }