black mud (English, noun)
expansion: black mud (countable and uncountable, plural black muds)
Senses:
glosses: Used other than figuratively or idiomatically: see black, mud.
tags: countable
uncountable
glosses: Reduced mud found below the surface of sediments in lakes and rivers, the blackness of which is caused by the occurrence of metal sulphides.
tags: countable
uncountable
Forms:
form: black muds
tags: plural