French kiss vs soul kiss

French kiss and soul kiss both are nouns.

Word	Noun	Adjective	Verb	Adverb
French kiss	Yes	No	No	No
soul kiss	Yes	No	No	No

As nouns, French kiss and soul kiss are synonyms defined as:

French kiss and soul kiss: an openmouthed kiss in which your tongue is inserted into the other's mouth

Other synonyms of French kiss include deep kiss.

French kiss (noun)	soul kiss (noun)
an openmouthed kiss in which your tongue is inserted into the other's mouth	an openmouthed kiss in which your tongue is inserted into the other's mouth