Certain words not showing meaning in look up

When I invoke the look up feature by selecting any word in any app the dictionary meaning is supposed to show which it does for certain words but for certain words only the Wikipedia link is shown. The dictionary meaning for the same word is shown in the main search bar when I swipe down in the Home Screen. I think words which have a wiki page to it only shows the Wikipedia page when it is supposed to show the dictionary meaning also. This is happening in my iPad and my iPhone so I think it is a glitch associated with iOS 15 including 15.2 as it did not happen with iOS 14.

I am attaching screenshots of all 3 cases