kiss vs smooch

kiss and smooch both are nouns.

Word	Noun	Adjective	Verb	Adverb
kiss	Yes	No	Yes	No
smooch	Yes	No	Yes	No

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

Other hyponyms of kiss include smack, deep kiss, French kiss, soul kiss, peck.

kiss (noun)	smooch (noun)
the act of caressing with the lips (or an instance thereof)	an enthusiastic kiss
a light glancing touch
any of several bite-sized candies
a cookie made of egg whites and sugar

kiss (verb)	smooch (verb)
touch with the lips or press the lips (against someone's mouth or other body part) as an expression of love, greeting, etc.	snuggle and lie in a position where one person faces the back of the others
touch lightly or gently