1. vb. [Drilling Fluids]

To mix with water and allow to react or yield in the water before use. Prehydrating is a common technique for incorporating bentonite in cement slurry or drilling mud. Prehydration may also be done for convenience in cementing operations to allow mixing of water containing the additives with powdered neat cement. Additives also may be prehydrated with mix water to avoid dry-blending the additives with cement.