title: Remove duplicate words/string from a tab separated file
body: <p>I want to remove duplicate words/strings from a large tab separated file using Linux commands.</p>
  
  <pre><code>names            john, cnn, mac, tommy, mac, patrick, ngc, discovery, john, cnn, adam, patrick
  cities            san jose, santa clara, san franscisco, new york, san jose, santa clara
  </code></pre>
  
  <p>The above is the file format, I want to retain the tabs and commas after removing the duplicate words.</p>
  
  <pre><code>names            john, cnn, mac, tommy, patrick, ngc, discovery, adam
  cities            san jose, santa clara, san franscisco, new york
  </code></pre>
  
  <p>Any help would be appreciated.</p>