Cannabis Glossary

Learn the lingo behind craft genetics! 

Have you ever wondered, “Just what in the world are these weed guys talking about? F2, S1, IBL?” Well worry not, we’re here to educate you on all the terminology used by cannabis experts! 

Welcome to our glossary! Here, we show you exactly what we’re talking about when we talk about our craft genetics. You’ll find these terms across our site, and most likely, other Cannabis Brand sites that take pride in their seeds. 

Bread Genetics Glossary

F1 – (Filial Generation)

This is the first generational step between the mother and father genetic of the same strain.

IE: Tokyo Tiramisu mother x Tokyo Tiramisu father = Tokyo Tiramisu F1

Time Capsule Top Down portrait

F2 and Beyond

This term represents the number of generational steps a mother and father have been hunted and then crossed from the same genetic lineage. 

When we cross two F1 individuals (whether landraces, hybrid or polyhybrid varieties), we obtain the second filial generation or F2, and so on with next generations, F3, F4, etc. The second filial generation often gives a more heterogeneous offspring than the F1; we can expect 25% to resemble parent A, 25% to resemble parent B and 50% will be a mixed expression of traits from both parents.


The acronym S1 refers to the first filial generation produced as a result of crossing the plant with itself.

This is achieved by a range of techniques aimed at reversing the sex of the selected female plant, getting it to produce male pollen and using it to pollinate itself. If it’s done properly, we get feminized offspring with the same genotype of the parent used.
Flowerpot lil dumpling

Bx1, Bx2 and Beyond 

Backcrossing is a technique used by Bread to reinforce certain genetic traits. 

This is done by crossing one of the progeny (F1, F2…) with one of the original parents (recurrent parent) which has the desired trait. To have an even more stable expression of the desirable trait, you can cross the BX1 again with the recurrent parent to have a BX2 (squaring) and so on with BX3 (cubing), BX4, BX5 etc 

Stacked Sundae Driver Possibly maybe not

IBL –  (In-Bred line)

Backcrossing is a technique used by Bread to reinforce certain genetic traits. 

This means that the cross was made using plants with almost identical genotype (inbreeding). Years of crossing very specific F1, F2, F3 and so on generations go into making a lineage like this. There is a lot of work behind IBL’s, as a large population of pure specimens had to be used to select the correct parents. In addition, our breeders at Bread must fight against inbreeding depression, the result of crossing parents with very similar genetic information. The reward for this job made properly is a highly stable and predictable seed variety. 

Nugsography photo (40 of 52)


Also known as landraces or purebreds, pure cannabis varieties have been the basis of cannabis breeding over the past decades.

These species are endemic to a geographical area, where they have developed without having been crossed (hybridised) with other varieties. Also known as “Mother” strains.

Fruity Flower Pot Portrait 3


In the cannabis world, heirloom strains are those that have existed for generations.

 They are considered to have pure genetics because they have never been crossbred with any other strains. These strains developed through natural pollination by wind, animals, and even humans. At Bread, ALL of our genetics are pollinated naturally, as we do not reverse, force, or self pollinate. A Heirloom strain is one that has been passed down through human generations, stabilized and bred for absolute uniqueness. 

Gorilla Breath-01047