Okay, but iris does have two meanings and sometimes you need to be specific in your queries. Your original query would not have been perfect if you were in fact wondering about the flower. "what is an iris anatomy site:*.edu" is enough to bring up this as the first result:
Sidetrack, but I can recommend the Firefox/Chrome extension "Don't Track Me Google" which cleans up Google result links to be the actual URL, without Google's tracking redirect.
https://www.umkelloggeye.org/conditions-treatments/anatomy-e...