Press CTRL+T to autoformat your code. Then you will see more clearly the problem. Just move the following code outside the for loop:

1.   int index = int(random(words2.size()));
2.   theWord = words2.get(index);
3.   println (theWord);

Some slight alterations...

1. void setup () {
2.   ArrayList <String> words = new ArrayList <String> ();
3.   String[] strings = loadStrings(selectInput());
4.   for (int i=0 ; i<strings.length; i++) {
5.     String[] choppedString = chopString(strings[i]);
6.     Collections.addAll(words, choppedString);
7.   }
8.   int index = int(random(words.size()));
9.   String theWord = words.get(index);
10.   println("There are " + words.size() + " words in this text file.");
11.   println("Word " + index + " has been randomly selected.");
12.   println("The word is: " + theWord);
13.   exit();
14. }
15.  
16. String[] chopString(String s) {
17.   String eliminate = "!#¤%&/1234567890+()=?`;:,._-*¨@'";
18.   String[] words = splitTokens(s, " " + eliminate);
19.   for (int i=0; i<words.length; i++) {
20.     words[i] = words[i].replace(eliminate, "");
21.     words[i] = words[i].toUpperCase();
22.   }
23.   return words;
24. }

GREAT!

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