Water

Water is the most common liquid in the Milky Way Galaxy and is crucial to survival for most carbon-based lifeforms.

In some regions of the Delta Quadrant, water is a scarse and valued commodity, traded amongst the Kazon and the Talaxians. In 2371, Captain Kathryn Janeway used water to bribe Maje Jal Jabin into revealing all information he had about the Ocampa and the Caretaker. (VOY episode: "Caretaker").