noun
dyer's knotweed; Persicaria tinctoria
A plant used historically to produce indigo dye. Often discussed in the context of traditional dyeing or botany.
See also: 藍
タデアイは藍染めの原料として栽培されていた。
Dyer's knotweed was cultivated as a raw material for indigo dyeing.
藍 (あい) refers to indigo dye or the indigo color itself, while タデアイ specifically refers to the plant species used to produce it.
Compound of 蓼 (たで, 'knotweed') and 藍 (あい, 'indigo'). The exact historical derivation is uncertain, but the name directly describes the plant's use in indigo production.