spoken language vs oral communication

spoken language and oral communication both are nouns.

Word	Noun	Adjective	Verb	Adverb
spoken language	Yes	No	No	No
oral communication	Yes	No	No	No

As nouns, spoken language and oral communication are synonyms defined as:

spoken language and oral communication: (language) communication by word of mouth

Other synonyms of spoken language include language, speech, speech communication, spoken communication, voice communication.

spoken language (noun)	oral communication (noun)
(language) communication by word of mouth	(language) communication by word of mouth