semillon 

Half a hard on (erection). Semi-on. Half mongrel. Pronounced like the white wine grape

I can't go out with this semillon, I'll have to wait a bit.

semillon by badpuppy September 26, 2005

semilong 

Not a full erect penis, but quite almost there.

Erika took off her top and had some good looking boobies that i got a Semi then decided to blow me and got a long good one. Semilong!

semilong by Will Sermon December 20, 2016