1. n. []

A drilling fluid (mud) in which water or saltwater is the major liquid phase as well as the wetting (external) phase. General categories of water-base muds are fresh water, seawater, salt water, lime, potassium and silicate. Subcategorizes of these abound.

Synonyms: water-based drilling fluid

See related terms: lime mud,  low-solids mud,  low-solids, nondispersed mud,  potassium mud,  saltwater mud,  spotting fluid