Variation
The concern grouping the categorical, SELECTABLE option axes a product comes in — most universally its size (and the system that size is expressed in). Per A9 a variation axis is an ordinary cardinality-many token property, never a SKU-grid or a qualified host: the property declares the axis exists and its value-domain; the catalogue selects the buyable cells (each cell's realised price/stock/image is a downstream offer row, L1). The other universal variation axes — color and material — are held in the measurement concern (intrinsic descriptors that are also variation axes); kind-specific axes (flavor, storage-capacity, fit, ...) live on the kind tree (Axis K). The orthogonal concern axis (L6), never a product kind.
2 questions in all: 2 answered from a set list (size and size system).
The concern grouping the categorical, SELECTABLE option axes a product comes in — most universally its size (and the system that size is expressed in). Per A9 a variation axis is an ordinary cardinality-many token property, never a SKU-grid or a qualified host: the property declares the axis exists and its value-domain; the catalogue selects the buyable cells (each cell's realised price/stock/image is a downstream offer row, L1). The other universal variation axes — color and material — are held in the measurement concern (intrinsic descriptors that are also variation axes); kind-specific axes (flavor, storage-capacity, fit, ...) live on the kind tree (Axis K). The orthogonal concern axis (L6), never a product kind.
| size | ◇token |
| size system | ◇token |