The Google Dictionary website was terminated on August 5, 2011 after part of its functionality was integrated into Google Search using the define: operator.
It was believed that, until August 2010, Google used definitions from CollinsCOBUILD. COBUILD entries were easy to recognize by their characteristic full-sentence definitions as well as rather cryptic grammar codes such as [N-VAR], which in Google Dictionary went unexplained. In August 2010, a blog site reported that Google Dictionary switched from the Collins COBUILD Advanced Learner's English Dictionary to the Oxford Pocket Dictionary of Current English as its English definitions provider. This report, although close, was not quite accurate, as in fact the content now came from another Oxford dictionary, the Oxford American College Dictionary. As of 5 August 2011 (2011-08-05)[update], Google Dictionary was discontinued as a separate service, although similar results have been incorporated into the Google search sidebar. However, this has resulted in a controversy over the way in which Google shut down the service without any warning. Moreover, the "Starred Words" feature became unavailable at the same time, without any opportunity for users to back up their starred words. Many users have expressed their disappointment with the sudden discontinuation of the service on Google's Help Forum. By September, the Starred Words were available again by accessing the list directly using the URL http://www.google.com/dictionary/wordlist but was gone again on 21 October 2011.