breath vs aspiration

breath and aspiration both are nouns.

Word	Noun	Adjective	Verb	Adverb
breath	Yes	No	No	No
aspiration	Yes	No	No	No

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

breath: the process of taking in and expelling air during breathing
aspiration: the act of inhaling; the drawing in of air (or other gases) as in breathing

Other hyponyms of breath include breathing out, exhalation, expiration, breathing in, inhalation, inspiration, intake.

breath (noun)	aspiration (noun)
the process of taking in and expelling air during breathing	the act of inhaling; the drawing in of air (or other gases) as in breathing
an indirect suggestion	a will to succeed
a slight movement of the air	a manner of articulation involving an audible release of breath
the air that is inhaled and exhaled in respiration	a cherished desire
a short respite