This is a list of all base, unenchanted clothing in Morrowind.
Enchant point values: Note that the Enchant values shown here are as used in-game. A fraction value shown here will be displayed truncated in-game. The construction set uses these values times ten for increased precision.
Gold–Enchant ratio: As a rule of thumb, the gold value of clothing is twice its Enchant points. Exceptions are the Imperial Templar Belt and Gondolier Shirt (underpriced for their enchantability, which is slightly above Expensive level), and the Imperial Belt, Indoril Belt, Imperial Skirt, and Imperial Templar Skirt (all over-priced, with 0.5 enchantment points, which should have translated to a value of 1 septim).
Gender neutrality: Most clothing, like armor, in the game can be worn by either gender, though the meshes of some are clearly designed for one gender or the other and will look funny if not on the right one (e.g. the red and black common shirt looks distorted on a woman). Some of the items have highly distinct meshes for each gender; for example, a shirt that visibly is a shirt–vest combo on a male may appear as a similar shirt–bodice combo on a female.
Compatibility: Skirts and pants are not mutually exclusive; you can wear both at the same time. Two clothing items, gloves and shoes, cannot be worn with their armor equivalents (gauntlets/bracers, and boots, respectively); these are the only clothing–armor incompatibilities. Only one of each item may be worn at any given time, except for rings (you can equip two).
Race restrictions: Shoes (like boots) cannot be worn by the beast races (Khajiit and Argonian), only by the various human and elf varieties.
Enchantment effects and equipping: A Constant Effect item must be equipped for its effect to be active. It is not necessary to manually equip an item to use a Cast When Used enchantment it has; simply select it from Magic window, and cast in magic mode (versus weapon mode). Note that this may replace a previously equipped item of the same sort (it will definitely do so for anything but rings). If a specific item is desired to be worn most of the time, it must be re-equipped after using another item of the same sort that has replaced it as the equipped item of that type. An item with only a Constant Effect enchantment does not appear in the Magic window, so it must always be manually equipped from the Apparel window. Cast When Strikes enchantments do not apply to clothing items.
Visibility: Pants, shirts, and gloves are worn under armor. Skirts are worn over pants, greaves, and sometimes the tops of boots. Robes cover everything but large pauldrons, and tips of boots/shoes and gauntlets/gloves (and of course helms and shields). Rings and belts are not visible on NPCs, nor on the player character's "paper doll" in the inventory screen, but only as inventory icons, or as idle items on the ground or another surface.
On companions: A companion NPC with inventory sharing will benefit from a Constant Effect enchanted clothing item. It is unclear under what conditions their AI will utilize Cast When Used enchantments, if at all. Companion AI is limited (e.g., some will take a Restore Health potion but only during combat, will not take any Fortify potion, and will use some scrolls while ignoring others), so do not depend upon them using Cast When Used items, or doing anything else clever. A very useful Constant Effect for a companion is Water Breathing, especially if you do not have a good target/touch spell for this; companions will generally follow you underwater until they drown (you'll hear them gurgling when they are running out of air). If a companion has a Constant Effect item, be aware that if you give them another item of the same clothing type that has a higher gold value, they will equip that instead for as long as they have it in their inventory.
Merchants: As with armor, if you sell a merchant (who buys and sells clothing) a clothing item that is worth more than what they are wearing, they'll equip the better item you've sold them, and it will not be among the items they have for sale (though what they were wearing before will be).
Note: Belts are not visible on the player or NPCs. Visibly apparent belts on characters are actually part of pants, shirts, robes, or armor.
Note: You cannot wear gloves and gauntlets or bracers at the same time.
Note: May be worn with a skirt. (British English: "trousers" are what is meant here, not "underpants".)
Note: You can wear two rings at the same time. Rings are not visible on the player or NPCs.
Note: Worn over other clothes and most armor.
Note: You cannot wear shoes and boots at the same time. Beast races, such as Argonians and Khajiit, cannot wear either.
Note: You can wear skirts as any race or gender (males may think of them as kilts or pteruges if they like). May be worn with pants.