noun which may take the genitive case particle 'no', noun
threefold; folded in three
Describes something folded into three parts, such as a letter, brochure, or mattress. Often used as a noun or with の to modify another noun.
三つ折りのパンフレットを作成した。
We created a tri-fold brochure.
手紙を三つ折りにして封筒に入れる。
Fold the letter in three and put it in the envelope.
Means folded in two (bifold), while 三つ折り is folded in three (trifold).
Compound of 三つ (three) and 折り (folding), from the verb 折る (to fold).