suggestion vs idea

suggestion and idea both are nouns.

Word	Noun	Adjective	Verb	Adverb
suggestion	Yes	No	No	No
idea	Yes	No	No	No

As nouns, idea is a hypernym of suggestion; that is, idea is a word with a broader meaning than suggestion:

Other hypernyms of suggestion include thought.

suggestion (noun)	idea (noun)
the act of inducing hypnosis	the content of cognition; the main thing you are thinking about
an idea that is suggested	your intention; what you intend to do
the sequential mental process in which one thought leads to another by association	an approximate calculation of quantity or degree or worth
a proposal offered for acceptance or rejection	a personal view
persuasion formulated as a suggestion	(music) melodic subject of a musical composition
a just detectable amount