encephalon vs rhombencephalon

encephalon and rhombencephalon both are nouns.

Word	Noun	Adjective	Verb	Adverb
encephalon	Yes	No	No	No
rhombencephalon	Yes	No	No	No

encephalon (noun)	rhombencephalon (noun)
that part of the central nervous system that includes all the higher nervous centers; enclosed within the skull; continuous with the spinal cord	the posterior portion of the brain including cerebellum and brainstem