eating vs ingestion

eating and ingestion both are nouns.

Word	Noun	Adjective	Verb	Adverb
eating	Yes	No	No	No
ingestion	Yes	No	No	No

As nouns, ingestion is a hypernym of eating; that is, ingestion is a word with a broader meaning than eating:

eating: the act of consuming food
ingestion: the process of taking food into the body through the mouth (as by eating)

Other hypernyms of eating include consumption, intake, uptake.

eating (noun)	ingestion (noun)
the act of consuming food	the process of taking food into the body through the mouth (as by eating)