Beckett Mariner applying lubricant to a turbolift
A lubricant was a chemical substance used to reduce friction between two surfaces.
Data occasionally ingested a semi-organic nutrient suspension in a silicon-based liquid medium to lubricate his bio-functions. His circulatory system also produced biochemical lubricants. (TNG: "Deja Q", "Birthright, Part I")
While playing Insurrection Alpha in 2373, Lieutenant Tom Paris had the holographic Chakotay so suspicious of his motives that he assigned him to lubricate the warp plasma manifolds. (VOY: "Worst Case Scenario")
On California-class starships, turbolift lubing was considered one of the worst jobs on the ship, along with carbon filter maintenance and holodeck waste removal. In 2380, Ensign Beckett Mariner was assigned to turbolift lubing on the USS Cerritos, which became dangerous when Lieutenant Shaxs used the turbolift while she was still on top of it. (LD: "Moist Vessel")
To be "lubricated" was Earth slang for alcohol intoxication. During a diplomatic reception on USS Voyager in 2375, Tom Paris observed of visiting Kadi Ambassador Tomin: "That guy's so lubricated he'll laugh at anything." (VOY: "Someone to Watch Over Me")