peak vs brow

peak and brow both are nouns.

Word	Noun	Adjective	Verb	Adverb
peak	Yes	No	Yes	No
brow	Yes	No	No	No

As nouns, brow is a hyponym of peak; that is, brow is a word with a more specific, narrower meaning than peak:

Other hyponyms of peak include hilltop, pinnacle, mountain peak.

peak (noun)	brow (noun)
a brim that projects to the front to shade the eyes	the part of the face above the eyes
the top or extreme point of something (usually a mountain or hill)	the arch of hair above each eye
the highest point (of something)	the peak of a hill
the most extreme possible amount or value
a V shape
the highest level or degree attainable; the highest stage of development
the period of greatest prosperity or productivity

peak (verb)	brow (verb)
to reach the highest point; attain maximum intensity, activity