Private parts (either gender) with a particularly bad odour.
Don't go down on him, he has a smelly nelly!
by Meme Princess June 30, 2016
Can you define these popular missing words?
When you eat out someones asshole, and they fart in your face.
Last night when me and Samatha did it, she wanted me to give her a Smelly Nelly, it was so hot!
by Jakeypooandblackkid October 18, 2011