huntsman's horn vs huntsman's horns

huntsman's horn and huntsman's horns both are nouns.

Word	Noun	Adjective	Verb	Adverb
huntsman's horn	Yes	No	No	No
huntsman's horns	Yes	No	No	No

As nouns, huntsman's horn and huntsman's horns are synonyms defined as:

huntsman's horn and huntsman's horns: pitcher plant of southeastern United States having erect yellow trumpet-shaped pitchers with wide mouths and erect lids

Other synonyms of huntsman's horn include Sarracenia flava, trumpets, yellow pitcher plant, yellow trumpet.

huntsman's horn (noun)	huntsman's horns (noun)
pitcher plant of southeastern United States having erect yellow trumpet-shaped pitchers with wide mouths and erect lids	pitcher plant of southeastern United States having erect yellow trumpet-shaped pitchers with wide mouths and erect lids