The name of this tea canister is said to be derived from the play on word with 'koi' meaning both 'deep' and 'love,' (double entente/pun) while the color of the glaze of this tea canister is in a unique 'koi' amber (meaning deep amber); a tanka (thirty-one syllables' poem) from Manyoshu (Collection of Ten Thousand Leaves) includes the word 'koi' in its phrase, 'Mikarisuru Karihano Onono Narashiba no Nareha masarade Koi zo masareru,' then the word 'Narashiba' was taken from this tanka for the name of this tea canister.
釉色が濃いアメ色で、これを「恋」にかけて万葉集の「御狩する狩場の小野の楢柴の汝はまさらで恋ぞまされる」の歌に因みこの名になったとされる。