1. n. [Formation Evaluation, Drilling Fluids]

The liquid that passes through a filter cake from a slurry held against the filter medium, driven by differential pressure. Dynamic or static filtration can produce a filtrate.

Alternate Form: mud filtrate

See: bridging material,  calcium test,  chloride test,  dynamic filtration,  filtrate volume,  formaldehyde,  high-pressure, high-temperature filtration test,  low-pressure, low-temperature filtration test,  potassium ion,  relative filtrate volume,  spurt loss,  total hardness test