invade vs infest

invade and infest both are verbs.

Word	Noun	Adjective	Verb	Adverb
invade	No	No	Yes	No
infest	No	No	Yes	No

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

invade: march aggressively into another's territory by military force for the purposes of conquest and occupation
infest: invade in great numbers

Other hyponyms of invade include overrun.

As verbs, invade and infest are synonyms defined as:

Other synonyms of invade include overrun.

invade (verb)	infest (verb)
march aggressively into another's territory by military force for the purposes of conquest and occupation	invade in great numbers
penetrate or assault, in a harmful or injurious way	live on or in a host, as of parasites
to intrude upon, infringe, encroach on, violate	occupy in large numbers or live on a host
occupy in large numbers or live on a host