Polyhybrid

Polyhybrid refers to a cross involving more than two parental lineages — or, more broadly, an offspring whose ancestry derives from multiple distinct hybrid sources that are themselves already hybridized and genetically heterogeneous. The term combines Greek poly- ("many") and hybrid. In classical genetics, a "polyhybrid cross" denotes a cross heterozygous at many loci simultaneously, extending Mendel's dihybrid/trihybrid concept. In cannabis, virtually all modern commercial cultivars — Girl Scout Cookies, Gorilla Glue, OG Kush derivatives — are polyhybrids descending from multiple layered crosses of previously hybridized lineages (Clarke & Merlin 2013; Lynch et al. 2016). Polyhybrid ancestry explains why commercial "Sativa"/"Indica"/"Hybrid" labels fail to predict genetic identity (Sawler et al. 2015; Schwabe et al. 2021; Watts et al. 2021), why offspring from a single polyhybrid seed pack exhibit dramatic phenotypic variability, and why stabilization via IBL or BX strategies is rarely pursued commercially. → See also: Hybrid, F1, F2, IBL, Cultivar.