Reversed, reversal, and reversing is a term used in cannabis breeding. Reversing a strain involves applying mutagenic chemicals to a female plant to make it produce pollen. Pollen is only produced naturally by males. Breeders often reverse a plant to use the pollen from that specific plant in a breeding project. The offspring of a plant reversed and bred to itself is called an ‘S1,’ as in ‘Self 1.’ For example, ‘I reversed that dope Runtz cut and now I have a bunch of S1s to hunt through, bro.’