i Register
In some senses, mucid is marked as archaic, figuratively. Watch for register when choosing this word.
adj
Musty; mouldy; slimy or mucous.
the incessant flurried movement of the flexuous lips, the little spasmodic cough, the mucid vacancy of the shell-fish-like eyes with their inflamed rims, pointed, significantly enough to discrimination, to one clear explanation of her aspect and condition.
Rotten, bad, worthless.