1. n. [Well Completions]

A thin nonelectric cable used for selective placement and retrieval of wellbore hardware, such as plugs, gauges and valves located in sidepocket mandrels. Valves and sleeves can also be adjusted using slickline tools. Partially collapsed tubing can be repaired using a tubing swage on slickline.

See: side pocket mandrel

2. n. [Well Workover and Intervention]

A single-strand wireline used to run and retrieve tools and flow-control equipment in oil and gas wells. The single round strand of wire passes through a stuffing box and pressure-control equipment mounted on the wellhead to enable slickline operations to be conducted safely on live wellbores.