The cell or cells that are currently active because the player is in/near them. When the player is in an interior this is a single cell. When the player is in an exterior, it is a 3x3 grid of cells centered on the player.
A creature or NPC.
Alternatively the Abecean Isles project or artificial intelligence.
When two meshes intersect, they are said to be bleeding into each other.
"Caspering" is when part of a mesh with no backfaces, such as the top of a column or the outside of a room tile, is visible from an angle which the player can reach without console commands. It's different from floating because even totally solid meshes, like books, can float, and even correctly placed meshes can casper if they don't have the right neighbors. The word "caspering" comes from an old American comic book/cartoon series called "Casper the Friendly Ghost." The character is partially see-through, and a movie based on the comics came out in 1995, so it was a familiar reference in the English-speaking TES3 modding community back in the day.
Bethesda Softworks Archive. A file containing meshes and textures.
EPoS / EPS
Elder Scrolls Master. A master file on which other master files and plugins can depend. Composed of records.
Elder Scrolls Plugin. A plugin file dependent on a master file. Composed of records.
An object in the world that defies gravity. This is a common issue that should be reported so it can be fixed.
A 3D model.
MGE / MGE-XE
The Morrowind Modding Community. A Discord server.
The Morrowind Optimization Patch. A mesh replacer that aims to improve performance while fixing issues with the vanilla meshes.
Project Tamriel Rebuilt
Portmanteau of Project Tamriel and Tamriel Rebuilt. Used to refer to both projects simultaneously.
An object in the world; an instance. Called a reference because they reference a base record. Each reference also has its own data, separate from the shared base. For example: ownership, locks and traps, position, rotation, scale, etc.
Every reference has a number that uniquely identifies it within a file, the "RefNum". These numbers are not unique across different files. When loading the game, RefNums are combined with the index of the file that contains them in the load order to create an identifier that is unique across all files. These identifiers are not stable because the load order can change. When loading a file in the CS, a similar thing happens. Except in this case the load order is the list of master files the file depends on. This is the reason "plugins cannot edit/override plugins". Note that two plugins can still define a record with the same ID, overriding one another.
S:HotN / SHotN
T_D / TD
The Elder Scrolls.
The Elder Scrolls III: Morrowind. A way to refer to the game that is less ambiguous than "Morrowind" which could also refer to the province.
The Elder Scrolls Construction Set. The editor used to create plugin files.
An image file used by a 3D model.