1. The overground drive for a reciprocating piston pump installed at a borehole (e.g. an oil well)
   - nodding donkey

Encyclopedia: Pump jack

• unassertiveness
• unassignable
• unassigned
• unassisted
• unassuming
• unassumingly
• unassumingness
• unassured
• unasterisked
• unattached
• unattackable
• unattainable
• unattainableness
• unattainably
• unattended
• unattentive
• unattired
• unattractive
• unattractively
• unattractiveness
• unattributable
• unau
• unauthentic
• unauthorised
• unauthorised absence