What is “Top”? and What does “Toppin'” mean?
The slang term “Top” is a noun and “Toppin'” is a verb, they both originated in New York as a reference to Fellatio.
Top means head or a blowjob. Top is also an acronym for Tongue on Penis.
Toppin' means giving head or a blowjob.
Read: What does “Jawn” mean?