eyecup vs eyebath

eyecup and eyebath both are nouns.

Word	Noun	Adjective	Verb	Adverb
eyecup	Yes	No	No	No
eyebath	Yes	No	No	No

As nouns, eyecup and eyebath are synonyms defined as:

eyecup and eyebath: a small vessel with a rim curved to fit the orbit of the eye; use to apply medicated or cleansing solution to the eyeball

Other synonyms of eyecup include eye cup.

eyecup (noun)	eyebath (noun)
(embryology) a two-walled cuplike depression that develops into the pigmented and sensory layers of the retina	a small vessel with a rim curved to fit the orbit of the eye; use to apply medicated or cleansing solution to the eyeball
a small vessel with a rim curved to fit the orbit of the eye; use to apply medicated or cleansing solution to the eyeball