Of course! If you’ve played Codenames and introspected on how you play you can see this in action. You pick a few words that feel similar and then try to justify them. Post-hoc rationalization in action.
Yes and you may search for other words that fit the rationalization to decide whether or not it's a good one. You can go even further if your teammates are people you know fairly well by bringing in your own knowledge of these people and how they might interpret the clues. There's a lot of strategy in Codenames and knowledge of vocabulary and related words is only part of it.