flood vs swamp

flood and swamp both are nouns.

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

As verbs, swamp is a hyponym of flood; that is, swamp is a word with a more specific, narrower meaning than flood:

Other hyponyms of flood include flow, deluge, inundate, submerge, drench.

As verbs, flood and swamp are synonyms defined as:

Other synonyms of flood include deluge, inundate.

flood (noun)	swamp (noun)
the act of flooding; filling to overflowing	low land that is seasonally flooded; has more woody plants than a marsh and better drainage than a bog
a large flow	a situation fraught with difficulties and imponderables
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)	swamp (verb)
cover with liquid, usually water	fill quickly beyond capacity; as with a liquid
become filled to overflowing	drench or submerge or be drenched or submerged
fill quickly beyond capacity; as with a liquid
supply with an excess of