The duim (meaning "thumb," but best translated as inch) was a unit of length in the old Dutch system of lengths. It was intended to be about the width of the top phalanx of the thumb of an adult man. The length of the duim varied from place to place; Cardarelli gives the Amsterdam voet (which he calls "voeten," actually the plural form of the word) as 0.2830594 m = 11.1440709 in. = 0.9286726 ft , and the duim (which he calls "duime") as one twelfth of that, which would make it 0.02358828 m = 0.9286726 in. .