What does Comedogenic mean?

For those of you with Adult Acne, this is real information you don't want to miss!

I’m sure you’ve seen this term before.  
Comedogenic.  
Let's break it down;  

comedo = an impaction of varying size containing a mixture of sebum (fancy name for our skin’s oil) and dead skin cells, often known as a “blackhead”;  

genic = creating.