Hi Pine,
Google's underlying database is called Knowledge Graph, and
some people call it that. Microsoft Bing's similar knowledge base is called Satori Knowledge Base. Looks like Google calls the sidebar a
Knowledge Panel (original
source).
I would've called it search summary, but some people seem to use that to refer to the snippets under the title/link for a result.
"Knowledge panel" seems to be reasonably generic, unambiguous, and definitely understandable with some minimal explanation. A few quick googles show that both "knowledge panel" and "knowledge graph" are being
genericized, and you can find people using both when discussing Bing, though Microsoft probably don't use either term.
Also of note, while a lot of info in Google's knowledge panel comes from Wikipedia, but not all of it, so "Wikipedia sidebar" would not be quite accurate.
Hope that helps,
—Trey