WCS Glossary
- Mill
- Mist Drilling
- Momentum
- Montmorillonite
- Moody Diagram
- Motor
- Motor Actuators Electric/Electronic
- Mousehole
- Mpd Operations Matrix
- Mud
- Mud Acid
- Mud Balance
- Mud Cap
- Mud Density
- Mud Flow Indicator
- Mud Gas Separator
- Mud/Gas Separator (MGS)
- Mud Logging
- Mud Pit
- Mud Pump
- Mud Return Line
- Mud Weight
- Multi-Phase Flow
- Multi-stage Pump
- Multiphase / Low Head
- Multiple Completion