A dubbeltje () is a small former Dutch coin, originally made of silver, with a value of a tenth of a Dutch guilder. The current 10-euro-cent coin that in circulation today in the Netherlands is also sometimes called a dubbeltje.
The name "dubbeltje" is the diminutive form of the Dutch word "dubbel" (Dutch for "double") because it was worth two stuivers. When the decimal system came to the Netherlands (about 1800) the 10-cent coin was named a "dubbeltje". In Dutch slang, a dubbeltje was named a beisje, from Dutch-Yiddish beis, the value of two stuivers. Automatic translation from Dutch to English often translates "dubbeltje" as "dime".
The central opening in a CD is exactly the size of a dubbeltje (15 mm). Joop Sinjou, head of Philips audio products development, said that "De snelste beslissing in de ontwikkelingsfase was over de diameter van het gat in de CD. Ik legde een dubbeltje op tafel en dat werd de maat." ("The fastest decision in the development phase was about the diameter of the hole in the CD. I put a dubbeltje on the table and that was the size.") The same form factor with the dubbeltje-sized center was carried over on newer disc formats such as DVD and Blu-ray.
There are Dutch sayings about the dubbeltje:
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