blow vs impact

blow and impact both are nouns.

Word	Noun	Adjective	Verb	Adverb
blow	Yes	No	Yes	No
impact	Yes	No	Yes	No

As nouns, impact is a hypernym of blow; that is, impact is a word with a broader meaning than blow:

blow (noun)	impact (noun)
a powerful stroke with the fist or a weapon	influencing strongly
forceful exhalation through the nose or mouth	the violent interaction of individuals or groups entering into combat
street names for cocaine	the striking of one body against another
an impact (as from a collision)	a forceful consequence; a strong effect
an unpleasant or disappointing surprise
an unfortunate happening that hinders or impedes; something that is thwarting or frustrating
a strong current of air

blow (verb)	impact (verb)
exhale hard	have an effect upon
free of obstruction by blowing air through	press or wedge together; pack together
melt, break, or become otherwise unusable
burst suddenly
shape by blowing
show off
cause to be revealed and jeopardized
allow to regain its breath
deposit eggs (of insects)
be in motion due to some air or water current
cause to move by means of an air current
leave; informal or rude
cause air to go in, on, or through
spout moist air from the blowhole
play or sound a wind instrument
make a sound as if blown
sound by having air expelled through a tube
provide sexual gratification through oral stimulation
spend lavishly or wastefully on
spend thoughtlessly; throw away
make a mess of, destroy or ruin
be inadequate or objectionable
be blowing or storming