hill vs tumulus

hill and tumulus both are nouns.

Word	Noun	Adjective	Verb	Adverb
hill	Yes	No	Yes	No
tumulus	Yes	No	No	No

As nouns, tumulus is a hyponym of hill; that is, tumulus is a word with a more specific, narrower meaning than hill:

hill: structure consisting of an artificial heap or bank usually of earth or stones
tumulus: (archeology) a heap of earth placed over prehistoric tombs

Other hyponyms of hill include barbette, barrow, burial mound, grave mound, embankment, snow bank, snowbank.

hill (noun)	tumulus (noun)
(baseball) the slight elevation on which the pitcher stands	(archeology) a heap of earth placed over prehistoric tombs
structure consisting of an artificial heap or bank usually of earth or stones
a local and well-defined elevation of the land

hill (verb)	tumulus (verb)
form into a hill