tanker vs motortruck

tanker and motortruck both are nouns.

Word	Noun	Adjective	Verb	Adverb
tanker	Yes	No	No	No
motortruck	Yes	No	No	No

As nouns, motortruck is a hypernym of tanker; that is, motortruck is a word with a broader meaning than tanker:

tanker: a motor vehicle designed to carry liquefied loads, dry bulk cargo or gases on roads.
motortruck: an automotive vehicle suitable for hauling

Other hypernyms of tanker include truck.

tanker (noun)	motortruck (noun)
a cargo ship designed to carry crude oil in bulk	an automotive vehicle suitable for hauling
a motor vehicle designed to carry liquefied loads, dry bulk cargo or gases on roads.
a soldier who drives a tank