frogbit vs frog's-bit

frogbit and frog's-bit both are nouns.

Word	Noun	Adjective	Verb	Adverb
frogbit	Yes	No	No	No
frog's-bit	Yes	No	No	No

As nouns, frogbit and frog's-bit are synonyms defined as:

frogbit and frog's-bit: European floating plant with roundish heart-shaped leaves and white flowers

Other synonyms of frogbit include Hydrocharis morsus-ranae.

frogbit (noun)	frog's-bit (noun)
European floating plant with roundish heart-shaped leaves and white flowers	European floating plant with roundish heart-shaped leaves and white flowers