betel vs betel leaf

betel and betel leaf both are nouns.

Word	Noun	Adjective	Verb	Adverb
betel	Yes	No	No	No
betel leaf	Yes	No	No	No

As nouns, betel and betel leaf are synonyms defined as:

betel (noun)	betel leaf (noun)
Asian pepper plant whose leaves are chewed with betel nut (seed of the betel palm) by southeast Asians	a leaf of a vine from the betel pepper
a leaf of a vine from the betel pepper