I type the word "ideation" a lot. I know, because every time I do attention is called to it in the form of a thin red squiggle. Most word processors think I am trying to spell "idealization", "detonation" or "delineation" which although sound like a good titles for a manifesto, have nothing to do with what I am writing about.
Frustrated at first, I think to myself "What do they mean 'Ideation' isn't a real word? We use it all day long at work! Don't these Word Processors know anything?"
It's not that Word Processors are not dumb, they are simply behind the times. Relatively speaking, design and it's lingo is still in it's early steps. Yeah, design has been around a while, but in the Public eye or Merriam Webster, it's all pretty new.
Companies like Apple paved the way for people to start saying "design" in regular speech back in the early 2000's, thanks large in part to their ads which emphasized being "designed" as something valuable. As more and more companies incorporate "design" into their finished products, they must use "design thinking" in the process of making them. Over time "ideation" (a made up word from back in the day with IDEO) will slowly begin getting circulated into conversations.
It's fun utilizing a word and way of thinking that is on the cusp of being added to dictionaries around the world. So rather than get frustrated at all the red squigglies peppering our design essays, we can use them as a reminder of just how new our field is.