breathing in vs intake

breathing in and intake both are nouns.

Word	Noun	Adjective	Verb	Adverb
breathing in	Yes	No	No	No
intake	Yes	No	No	No

As nouns, breathing in and intake are synonyms defined as:

breathing in and intake: the act of inhaling; the drawing in of air (or other gases) as in breathing

Other synonyms of breathing in include aspiration, inhalation, inspiration.

breathing in (noun)	intake (noun)
the act of inhaling; the drawing in of air (or other gases) as in breathing	the process of taking food into the body through the mouth (as by eating)
	the act of inhaling; the drawing in of air (or other gases) as in breathing
	an opening through which fluid is admitted to a tube or container