overflow vs run over

overflow is a noun but run over is not a noun.

Word	Noun	Adjective	Verb	Adverb
overflow	Yes	No	Yes	No
run over	No	No	Yes	No

As verbs, overflow and run over are synonyms defined as:

Other synonyms of overflow include brim over, overrun, well over.

overflow (noun)	run over (noun)
a large flow
the occurrence of surplus liquid (as water) exceeding the limit or capacity

overflow (verb)	run over (verb)
overflow with a certain feeling	injure or kill by knocking (someone or something) down and passing over the body, as with a vehicle
flow or run over (a limit or brim)	flow or run over (a limit or brim)