Well, reagrdless of any charts, I think that Sollozzo used the word in a derogatory way. He could have just as easily said "that idiot Clemenza" or "that skinny-assed Tessio" or "that psycho Sonny." The writers put that line in there to represent Sollozzo contempt for who he considered an enemy. Obviously, Clemenza's girth jumps right out at you if you are looking for a derogation term.

"Generosity. That was my first mistake."
"Experience must be our only guide; reason may mislead us."
"Instagram is Twitter for people who can't read."