Tanker
In starship classification, a tanker was a starship with a limited role. Similar in purpose to a freighter, tankers were designed to carry large amounts of bulk fuel or other liquid-type substances. 

Captain  commanded a  deuterium tanker during the 2140s and 2150s. During this time, he harassed the residents of the small deuterium mining colony operated by Tessic, taking the majority of the deuterium for his own ship. ()

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de:Tanker
ja:油槽艦
Spacecraft classifications