lubricator vs motor oil

lubricator and motor oil both are nouns.

Word	Noun	Adjective	Verb	Adverb
lubricator	Yes	No	No	No
motor oil	Yes	No	No	No

As nouns, motor oil is a hyponym of lubricator; that is, motor oil is a word with a more specific, narrower meaning than lubricator:

lubricator: a substance capable of reducing friction by making surfaces smooth or slippery
motor oil: oil used to lubricate the moving parts of a motor

Other hyponyms of lubricator include drilling fluid, drilling mud.

lubricator (noun)	motor oil (noun)
a substance capable of reducing friction by making surfaces smooth or slippery	oil used to lubricate the moving parts of a motor