proposal of marriage vs proposal

proposal of marriage and proposal both are nouns.

Word	Noun	Adjective	Verb	Adverb
proposal of marriage	Yes	No	No	No
proposal	Yes	No	No	No

As nouns, proposal of marriage and proposal are synonyms defined as:

Other synonyms of proposal of marriage include marriage offer, marriage proposal.

proposal of marriage (noun)	proposal (noun)
an offer of marriage	something proposed (such as a plan or assumption)
	the act of making a proposal
	an offer of marriage