I might be biased towards working with clear definitions though. For instance, from what I've read so far nobody makse a clear distinction between the terms "open-world" and "sandbox". Although if you take both terms literally, you just can't take them synonymously. Taking sandbox metaphorically, we think of a little child playing in an enclosed space with his toys and tools, out of a pure enjoyment of curiosity and creativity. Now exploration as can be found in an "open world" might be an aspect of curiosity, but it's not an aspect of the sandbox self. For a sandbox we require a certain level of creative interactivity with the game's world. And this level of interactivity is not given at all in open world games such as Flight Simulators and RPGs. In a similar fashion also nobody seems to use a agreeable definition of emergence.
Thank you. That kind of specificity clears things up, and enables a conversation. As Ashaman said, a challenge you face is that no two speakers or writers will necessarily agree on definitions of terms. Ashaman's suggestion that you check GDC Vault is a good one. The vault is usually open only to attendees of the most recent Game Developers Conference, unless the rules have changed, but money might be a way to unlock the vault too (I'm not sure). Very valuable material within. You should also check Gamasutra, but I assume you know that already. Also see if past issues of Game Developer magazine (gdmag) are accessible.
You can also simply explain (as you did today) what terms you are looking for definitions for, and this community can offer their own divergent opinions for you.