SearchWP Term Synonyms Extension
SearchWP offers insight into searches taking place on your site via the Search Stats link under the Dashboard menu in the WordPress admin. You might notice that a lot of people are searching for slight variants of keywords or abbreviations that aren’t getting the results you’re looking for. The SearchWP Term Synonyms Extension allows you to manually define synonym relationships in your index.
What’s more is you can have the synonyms completely replace the search term. If people are commonly searching for terms that simply aren’t (and never will be) in your index, you can replace them before searches are performed, getting the results your visitors are looking for.
After activating Term Synonyms, you can find the management of synonyms by navigating to the SearchWP Settings screen and clicking the link under the Extensions menu:
From there you can manage your Term Synonyms and add an extra level of relevancy to your content.
This is an extension of SearchWP Plugin. As to use this extension, you need to first install SearchWP Plugin.