Otoshidama-bukuro (envelopes for money) (お年玉袋)
Otoshidama-bukuro is an envelope in which you put money (mainly bills) when you give otoshidama (New Year's gift) on New Year's holidays.
It is generally made of paper and the size varies from about business cards to envelopes. It is sometimes called "pochi bukuro," which means "tip, gratuity" in Kansai dialect, shugibukuro (special envelope for monetary gifts) which was usually given to Japanese dancing girls in and around Kyoto (apprentice geigi or geiko). The word "pochi" means "a little bit" and originally showed an attitude of humbleness. There is a different opinion saying that it comes from English "spot" or French "petit," or changed "tama" (scrotum) to "pochi."