natural philosophy vs relativistic mass

natural philosophy and relativistic mass both are nouns.

Word	Noun	Adjective	Verb	Adverb
natural philosophy	Yes	No	No	No
relativistic mass	Yes	No	No	No

natural philosophy (noun)	relativistic mass (noun)
the science of matter and energy and their interactions	(physics) the mass of a body in motion relative to the observer: it is equal to the rest mass multiplied by a factor that is greater than 1 and that increases as the magnitude of the velocity increases