Unjack

jack to hold the same for treatment, and means acting automatically to unjack the shoe as the support or jack is moved outward on said table

Source: wiktionary

Jackup platforms of small dimensions are usually severely limited by weather conditions, since they are unstable and dangerous to unjack when wave heights are greater than a few feet.

Source: wiktionary

She gave it a go, with no luck. "I'm freezing. I've got to get back inside." "Then we're screwed. You can't." "Un-jack this fucking thing, I'm going in."

Source: wiktionary