Cokey referred to a heavy user of cocaine. Here are the meanings for the other key words in "Minnie the Moocher."

Hoochie-koocher was a term used for a trampy woman that would dance provocatively, show some skin,etc.

"Kick the gong around," refers to smoking opium in opium dens often located in Chinese neighborhoods within major cities of the time.

In the second verse of the song, Calloway uses the term jelly roll;" in the jazz context of the time, that phrase refers to a woman's genitals.

PS- Here is the second verse, as many people are only familiar with the first verse:

Now Min and Smokie, they started jaggin'
They got a free ride in a wagon
She gave him money to pay her bail
But he left her flat in the county jail

Whoooa, yeaaaah
Hey de he de he he
Whoa Whoa

Poor Min met old Deacon Lowdown
He preached to her that she ought to slow down
But Minnie wiggled her jelly roll
And Deacon Lowdown yelled, "Lord save my soul!"

Hi de hi de hi de hi
Ho de ho de ho de ho
Skiddley doodley doodly do
Skiddly diddly day

They took her where they put the crazies
Now poor Min's kicking up those daisies
You've heard my story this is her song
She was just a good gal, but they done her wrong

Hi de hi de hi de hi
Skooby de be do )
He de he de he de he
Whoa, Whoa Whoa

Poor Min, Poor Min, Poor Min.