overflow vs overrun

overflow and overrun both are nouns.

Word	Noun	Adjective	Verb	Adverb
overflow	Yes	No	Yes	No
overrun	Yes	No	Yes	No

As verbs, overflow and overrun are synonyms defined as:

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

overflow (noun)	overrun (noun)
a large flow	too much production or more than expected
the occurrence of surplus liquid (as water) exceeding the limit or capacity

overflow (verb)	overrun (verb)
overflow with a certain feeling	run beyond or past
flow or run over (a limit or brim)	seize the position of and defeat
	flow or run over (a limit or brim)
	invade in great numbers
	occupy in large numbers or live on a host