slang vs gull

slang and gull both are nouns.

Word	Noun	Adjective	Verb	Adverb
slang	Yes	No	Yes	No
gull	Yes	No	Yes	No

As verbs, slang and gull are synonyms defined as:

Other synonyms of slang include befool, cod, dupe, fool, put on, put one across, put one over, take in.

slang (noun)	gull (noun)
a characteristic language of a particular group (as among thieves)	mostly white aquatic bird having long pointed wings and short legs
informal language consisting of words and expressions that are not considered appropriate for formal occasions; often vituperative or vulgar	a person who is gullible and easy to take advantage of