Tutorial Tuesday: Google Search Operators - the Tilde

Not too long ago I was asked a question regarding Google’s search operators, specifically the tilde (~). The original question was, "Is the tilde really necessary in a Google search? If so, what exactly does it do? We understand it pulls similar results in theory but just typing a word will default to similar words as well."

My Answer

The tilde (~) is not really necessary in a Google search, although it can have its uses. The tilde functions as a synonym search, returning not only the search term you specified, but also terms that Google “thinks” are synonymous with the term. I’ve also read some sources that claim the ~ will return results of the term with alternate endings, similar to a root word search. However, in my testing, I have found that is not always or even necessarily the case.

Of note is that it’s Google itself that “chooses” what it thinks are synonyms, and while they sometimes make sense, in my testing they sometimes don’t, and they are also not exhaustive (in other words, the ~ does not appear to return ALL possible synonyms, just some).

Having said all of that, if I wanted to find someone with software development experience, I can search for ~develop. That returns the following words: developing, development, developer – which may be helpful.

However, if we try the same thing with ~design, we get results with matches of architecture and construction. Which may not be so helpful.

Because Google does automatically employ stemming, you can search for a term like develop and it will automatically return results of developer, developed, etc. However, some synonyms are not always conveniently words with alternate endings (as we saw in the case of ~design).

In fact, some words don’t stem to anything. Searching for software will only return the word “software” – because nothing stems off of it. However, if you use the tilde, it CAN be useful in that ~software will also return results of shareware, programs, drivers, and tools – but “application” is mysteriously missing.

Conclusion:

The tilde does have its uses, but it also comes with limitations. I do use it from time to time, just to see what Google is going to return as synonymous results, but if I find the synonymous results irrelevant, I simply drop the tilde.

Also – if you want to “turn off” Google’s auto-stemming for any particular search term, you can simply add a + sign immediately in front of your terms or phrases (e.g., +accountant), or you can use quotation marks to essentially achieve the same thing (e.g., “accountant”). That way, Google will not also return results of accountants or accounting if you are specifically targeting the word accountant.

About the Author:
Glen Cathey is the author of www.booleanblackbelt.com, a blog about sharing best practices for leveraging the Internet, job boards, resume databases, and social networks for sourcing and recruiting. With over 12 years of experience in the recruiting and staffing industry, he currently serves as the V.P. of Recruitment for a large staffing firm and trains hundreds of recruiters every year in the art and science of leveraging technology for talent identification and acquisition.

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Permalink Reply by Chaser on July 21, 2009 at 12:15pm

Thank you Glen =)

-Chase

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Permalink Reply by Will Branning on July 21, 2009 at 1:17pm

I appreciate the tips - anything to make searches more efficient is very welcome!

- Will Branning

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Permalink Reply by Glen Cathey on July 27, 2009 at 10:18pm

Thanks Chaser, Will, and Rayanne! Let me know if there is anything else you'd like me to cover.

Glen
www.booleanblackbelt.com

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Permalink Reply by Tasha Bergson-Michelson on July 30, 2009 at 4:07pm

Thanks for the great topic, Glen!   Sorry for the cross-post from Boolean Strings, and a bit long....

It is my understanding that the pseudo-thesaurus behind the tilde operator is developed as an automated function. When many people OR together the same words (e.g. [child | children | kid | kids]), or search on one and then another in quick succession (e.g., [child] then [children] then [kid] then [kids]), at a certain point Google "learns" that these words are somewhat synonymous. This process explains the gaps, or the possible mismatches or lack of matches (until very recently, for example, [~teen] had no related terms).   

You can use the tilde as a short-cut, but you should always check what kind of a short cut you are getting, first. Want to search on [~child]? First try NOTing out responses until you know what you are dealing with. I start with [~child -child] and keep adding terms until my search is [~child -child -kids -family -young -baby -children -children's -childhood], and I get the following error message: "Your search - ~child -child -kids -family -young -baby -children -children's -childhood - did not match any documents." Then, I know what I am getting when I use the tilde, and can edit my search accordingly. I might use [~child OR elementary], for example, as an element in some of my searches for how young students are learning search. (Note that this list has grown significantly in the past few months-I think that "baby," 'children's," and "childhood" are all new--and that "kidz" used to be returned as well, but is now gone, so someone must be editing the list at some point.)   

The tilde is a great tool when you know how it works, and I really appreciate that Glen took the time to experiment and demonstrate. It especially can help you avoid the 32-word limit on searches. As long as you master the tool, instead of letting it master you, it can certainly save you time in searches you run frequently.