'tanker' originates from the word 'tank,' which comes from the Portuguese word 'tanque,' meaning 'reservoir' or 'cistern.'

'tanque' transformed into the English word 'tank,' and eventually became the modern English word 'tanker' to describe a vehicle or vessel carrying liquids.

Initially, it meant 'a container for holding liquids,' but over time it evolved into its current meaning of 'a vehicle or vessel designed to transport liquids.'