One of the lesser-known tools used by searchers on Google has been the tilde sign (~) operator.
When you placed the tilde sign immediately in front of a keyword, Google would also include synonyms for that word in their search results. This was useful for webmasters determining additional keywords by seeing what words Google associates together.
Unfortunately, Google has quietly dropped support for the tilde sign in Google search results.
Google's Dan Russell confirmed the deprecation, as Google Operating System reported:
Yes, it's been deprecated. Why? Because too few people were using it to make it worth the time, money, and energy to maintain. In truth, although I sometimes disagree with the operator changes, I happen to agree with this one. Maintaining ALL of the synonyms takes real time and costs us real money. Supporting this operator also increases the complexity of the code base. By dropping support for it we can free up a bunch of resources that can be used for other, more globally powerful changes."
Hillary MacBain seems to be the first who noticed it had stopped working on June 15, 2013. It has also been removed from Google's Help Center article and that searchers using the tilde sign no longer see synonyms in their search. Now, searchers will only see the results for the keyword they used, as if the tilde sign was not included in the keyword search.
The tilde sign was included in the May 13, 2013 archive.org capture of the Help Center article, so the support was removed very recently. While the tilde sign was probably not used by very many people on it regular basis, it has been used since at least 2003 and it was very useful for webmasters.
There doesn’t seem to be any reason for Google to remove the tilde sign operator now. There was controversy a few years ago where the tilde sign was used with the word Scientology, and it also brought up a Wikipedia article for “cult”. However, there was nothing notable recently that hit the news that would prompt Google to remove it.
MacBain does note that the features still seems to be available as a Google Drive feature, and recommends this article for setting it up, for those who can’t live without the tilde operator. However, because it has been removed from Google search and their Help Center article, it would seem likely that it will go missing from Google Drive at some point in the future.