How to Look Up a Word Definition in iOS 11

iOS 11 includes a neat built-in dictionary feature that lets you quickly look up the definition of words on your iPhone or iPad, even if an internet connection is unavailable. It’s a handy recourse if someone breaks out a “big word” during a conversation, or you come across an expression in a book or on the web that you don’t quite understand. There are a couple of ways to access the dictionary