The Delenda Esta Club.
Sabbath? Some kind of thing that is a bit more broad, and different to the specific Jewish rules, related to Lauren Lee's Rest Days. But maybe not.
Asymmetric Justice.
Very Serious People/Doom Patrol.
An explanation of what Tier One, Tier Two, Tier Three, etc mean in your game reviews.
Belief In The Physical World (see What is the right phrase for "theoretical evidence"?).
Do you have this anywhere to peruse/edit/comment on? That's likely more efficient than suggestions from near-scratch in this post.
In the Ambrose Bierce vein, I'll propose :
Effective Altruism: the belief that one should appear as clever as possible when forcing our ideas of improvement on other people.
If the Glossary will have a way to link to specific words, that might be useful as well. (On LW, it wouldn't make for a very readable table of contents on the left, but the links would be useful.)
For each 'word', a link to a post that already explains them would also be useful, especially if it takes less time than writing out the glossary.
I've been working on a Glossary that will give short descriptions of concepts I've introduced, so people don't have to seek out entire posts to grok what they mean in context and then decide later if they'd like to know more. So far I've got Asymmetric Justice, The Delenda Est Club, Doom Patrol, Everything is Trying to Kill You, Easy Mode, Hard Mode, Perfect/Superperfect/Imperfect Competition, Immoral Maze, Maze Behaviors, Maze Levels, Slack, Out to Get You, Simulacra Levels, Sacrifice to the Gods, Very Serious People.
What other things should I make sure to include? (Post has been edited as I add things, answers below that suggest things that are in likely were helpful, thank you)
(Also any cool elegant/short definitions for the above or other Zvi-concepts are welcome, including Devil's Dictionary style versions)