My understanding is that Siri consults Apple Maps for "nearest hamburger joint" and the like.
Maybe I am misunderstanding, but perhaps you should post an example of your query to Siri? ? "Siri, where can I get an abortion?" - OR - "Siri, where is the nearest abortion clinic?" are very different questions, IMHO.
IF your issue has to do with a specific business being "mis-located", there are means to report this described in Get help with Maps on your iPhone, iPad, or iPod touch - Apple Support
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If you're a business owner and want to correct the information in Maps about one of your locations, sign in to Maps Connect. Learn more about how to use Maps on your iPhone, iPad, or iPod touch.
Last Modified: Sep 28, 2015