hollyhock vs mallow

hollyhock and mallow both are nouns.

Word	Noun	Adjective	Verb	Adverb
hollyhock	Yes	No	No	No
mallow	Yes	No	No	No

As nouns, mallow is a hypernym of hollyhock; that is, mallow is a word with a broader meaning than hollyhock:

hollyhock: any of various tall plants of the genus Alcea; native to the Middle East but widely naturalized and cultivated for its very large variously colored flowers
mallow: any of various plants of the family Malvaceae

As nouns, mallow is a hypernym of hollyhock; that is, mallow is a word with a broader meaning than hollyhock:

hollyhock: any of various plants of the genus Althaea; similar to but having smaller flowers than genus Alcea
mallow: any of various plants of the family Malvaceae

hollyhock (noun)	mallow (noun)
any of various tall plants of the genus Alcea; native to the Middle East but widely naturalized and cultivated for its very large variously colored flowers	any of various plants of the family Malvaceae
any of various plants of the genus Althaea; similar to but having smaller flowers than genus Alcea