robe vs abaya

robe and abaya both are nouns.

Word	Noun	Adjective	Verb	Adverb
robe	Yes	No	Yes	No
abaya	Yes	No	No	No

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

robe: any loose flowing garment
abaya: (Arabic) a loose black robe from head to toe; traditionally worn by Muslim women

Other hyponyms of robe include bathrobe, dressing gown, lounging robe, robe-de-chambre, kimono.

robe (noun)	abaya (noun)
any loose flowing garment	(Arabic) a loose black robe from head to toe; traditionally worn by Muslim women
outerwear consisting of a long flowing garment used for official or ceremonial occasions

robe (verb)	abaya (verb)
clothe formally; especially in ecclesiastical robes
cover as if with clothing