1. a mechanical device with a screw mechanism used for lifting heavy objects

Examples

• The mechanic used a jackscrew to lift the car for repairs.
• Construction workers positioned the jackscrew under the beam.
• The jackscrew can lift several tons when properly operated.
• She turned the handle of the jackscrew to raise the load.
• The old jackscrew was replaced with a hydraulic jack.
• Railroad workers used a jackscrew to align the heavy rail sections.