Marid
For the water jinn, see Chanti.
Marids (roughly Arabic "rebels") are a type of evil spirit in Islamic theology, comparable to shayatin (devils) and ifrit (rebellious jinn).
Etymology
In the Quran, marid is used as a descriptor—meaning rebellious—for devils.
Wa hifzam min kulli Shaitaanim maarid ("And as protection against every rebellious devil")
—Quran 37:7
Marids may be a type of evil jinn. Some claim them to be the mightiest of the evil jinn, and in some renditions of Arabian Nights the terms marid and ifrit (a class of jinn who are especially mighty and rebellious) are used interchangeably.
The term sometimes has associations with demons, giants, and divs.
D&D
Main article: Chanti
In D&D, marids are water genies, who lean Chaotic Neutral. I'm about 90% sure they're associated with water because marid is reminiscent to the word marine (coming from Latin mare "sea"). But marid is an Arabic word, not Latin. Marids have nothing to do with water.