I suppose you're badly misspelling adjacency list.  You don't want that.  All you need to do is make a dict called exits or something, and do:

room.exits["east"] = conservatory

or whatever.

This is kinda an adjacency list but usually by the time you're calling it an adjacency list you're talking about generic graph stuff which is massive overkill for anything you're doing.

I mean, it's just a super fancy way to say dict of exits.  You don't usually hear the term outside mathematical papers.  If you were on a reddit with people who don't know what muds are, they might have thought you were asking about the sorts of pathfinding needed by modern sighted games, which will probably use adjacency lists for stuff.  But a mud is just a dict mapping names of the exit to the room it goes to, really, possibly with some flags like "is a door", "is a closed door" etc.