flood vs flood out

flood is a noun but flood out is not a noun.

Word	Noun	Adjective	Verb	Adverb
flood	Yes	No	Yes	No
flood out	No	No	Yes	No

flood (noun)	flood out (noun)
the act of flooding; filling to overflowing
a large flow
light that is a source of artificial illumination having a broad beam; used in photography
the occurrence of incoming water (between a low tide and the following high tide)
the rising of a body of water and its overflowing onto normally dry land
an overwhelming number or amount

flood (verb)	flood out (verb)
cover with liquid, usually water	charge someone with too many tasks
become filled to overflowing
fill quickly beyond capacity; as with a liquid
supply with an excess of