Could someone please define what dark_"?" is and were exactly would it apply and wouldnt, the wikis arnt really any help on that. And if they cant be clearly defined then should they be invalidated? Worth noting that we do not have "light" tags so...

Dark is not among the colors that were kept during the previous body-color reorganization. Those should be aliased away, as far as I can see.

(We do have the dark_theme tag, but that one is aliased with black_theme, not separate.)

While on the subject: gold_* should probably be aliased to yellow_* asap. It's not distinct enough to keep, and someone might end up confusing it with gold_(metal). I'd suggest not listing it on the wiki, since that'll only make users tag it more, instead of the primary colors.

Actually dark_skin is still a fairly large tag.

Ruku said:
Could someone please define what dark_"?" is and were exactly would it apply and wouldnt[..]

tl;dr: 'dark' could be used in comparative contexts, i.e. darker than [something]

In addition to what everyone already said,

Dark_fur/ skin/ scales/ feathers/ goo/ carpace/ gas/ body ; invalidation?

dark_gas ?

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Also related is the discussion in forum #202365 - Genitalia colo(u)r discussion: Light/dark contrasts (Jul. 2016),

which is about dark(/light) genitals

(i.e darker than the surrounding body color/tone)

titanmelon said:
tl;dr: 'dark' could be used in comparative contexts, i.e. darker than [something]

In addition to what everyone already said,

the '[something]' part from the above phrase could refer to:

• average/expected values
• eg dark_skin

• as a literal comparative term, usually in reference to something present in the scene
• eg darkened_genitals

More detail:

• there was black_theme -> dark_theme as @Genjar mentioned
• darker than the average level of expected luminance

• dark_skin (applies usually to humanoids, as @hsauq mentioned)
• darker than the average expected skin tone

• dark_fu
• darker than the average expected fur tone [???]
• could be related to cool_colors/warm_colors, but for 'luminance' instead of color temperature

• dark_nipples
• see dark_skin

• dark_background
• see dark_theme

etc.

that all seems all too subjective(expected average) which is why im posting this because averages change from group to group, we did have this dabate recently over tints and shades concerning cyan and blue tints and shades that overlap with cyan or blue when someone wanted to alias all cyan tags to blue tags, id think there are no tags for actual color shades and tints other then grey and tan because it is all too ambiguous.

And as far as human skin goes, brown and black tags would fulfill that propose without being as ambiguous/subjective. and again we dont tag for light or lightened skin so why use dark/darken. Seems rather inconsistent in that regard.

changing white_theme to light_theme and black_theme to dark_theme also i dont quite agree with and find inconsistent, it would seem this was done based off western symbolic perception of light and darkness that might not be shared in east Asian societies. nether are all images that are black themed, dark in emotion.

PS: Gas like goo a body texture that is clearly visible but for what ever reason is not included and the body texture meta tag group instead lumped with body that is actualy for stuff that isnt distinct.

@Genjar
Do agree on removing gold thru that will have to be cleaned up extensively first before aliasing or invalidating sence not all posts would fit under yellow, some posts would have to go to orange while other that look more like copper go to tan...