1. n. [Drilling]

A telescoping joint at the surface in floating offshore operations that permits vessel heave (vertical motion) while maintaining a riser pipe to the seafloor. As the vessel heaves, the slip joint telescopes in or out by the same amount so that the riser below the slip joint is relatively unaffected by vessel motion.

Synonyms: travel joint

See: drilling riser

2. n. [Well Completions]

A completion component designed to accommodate tubing movement or length changes while maintaining a hydraulic seal between the production conduit and the annulus. The size or length of the slip joint depends on the wellbore conditions and completion characteristics.