Has anyone else noticed this kind of change?
Yes. But it almost seemed to be outsmarting itself.
I won't use the exact keywords here, because it mentions a product, but basically I was looking to purchase a service to digitally copyright my images, but I wanted to see if that service was easily cracked because I didn't want to spend money on something that wasn't going to work. So what I searched for (with an alteration to the keywords so as not to mention the product by name in this forum) was along the lines of:
"defeat digital marking"
Now, almost all of the top 10 results were for the company that sells this service. (Not indented - just multiple regular results).
Then there was a listing for a DJ with the name of marc, and the word "beats" (as in musical beats) was bold in the snippet, despite not being in my query.
So in this example, we saw the NAME Marc being a synonym for the noun mark (as in watermark or mark up), but more interesting to me was the word defeat was transposed to "beats" (a reasonable jump) but that it was referencing musical beats
as opposed to the related meaning of "to conquer"
So either the alg thinks that ALL instances of the word beats are synonyms of defeat, (we can probably test that out easily), or there must be some trigger that expands the scope of the matching synonyms when there is a dearth of pages that mention ALL the words on the same page.
Also, I wonder if anchor text from backlinks influences how well a site will rank for a synonym.
Supppose we have a site that is about widgets, and DOESN'T mention the word foo bar on there.
But we build a huge number of inbound links that use foo bar as the anchor text, even though it is not a common synonym of widgets.
Could we get that widget page to rank for foo bar based solely on the anchor text of inbound links? Could we get google to bold the word widgets in tne snippet when a searcher looks for foo bar?
(In reality, the page will probably be penalized - but I give this as an example to try and get ideas on how google LEARNS of synonyms.)