Stop Card: A card that does not draw any more cards from your deck, like Giant or Gold.
Striking the second sentence, I feel like this does get most of the way there and is not misleading. I am still open to other wordings, as this seems to have more gaps than other definitions. Also open to removal, if this entry is just not as helpful.
Pseudo-Trash: Remove cards from your deck without trashing them. For example, Island sets aside cards.
I am happy with this definition and example, but if people are confused by it or don't see the benefit of including it, I can remove it. It's on the bubble for me. There are now lots of cards that can pseudo-trash, which is why I thought it was worth including. Island, Native Village, Archive, Haven, Annex, etc. can pseudo-trash other cards. Reserve cards can pseudo-trash themselves.
Milling Provinces was also on the bubble, but the other side of it. AJD's proposed definition would also need the addition of remodeler so that's a two term requirement. Dud and payload: I didn't think a Dominion specific definition is any clearer than starting with the English dictionary definition of these words and then looking at context, so that's why I didn't include them. Open to inclusion if people can come up with helpful, simple definitions.