pearl diver vs pearler

pearl diver and pearler both are nouns.

Word	Noun	Adjective	Verb	Adverb
pearl diver	Yes	No	No	No
pearler	Yes	No	No	No

As nouns, pearl diver and pearler are synonyms defined as:

pearl diver and pearler: a diver who searches for molluscs containing pearls

pearl diver (noun)	pearler (noun)
a diver who searches for molluscs containing pearls	a diver who searches for molluscs containing pearls