Noundyer's knotweed (Persicaria tinctoria, used to produce indigo dye)

Nounwater pepper vinegar; vinegar infused and mixed with water pepper leaves, esp. served with salt-grilled sweetfish

NounPolygonaceae (knotweed or smartweed family of plants)

Expressions (phrases, clauses, etc.)some prefer nettles; there's no accounting for taste; every man to his taste