English translation of the Polish 'kilkanaście'

I am working on writing the students' grammar notes for a Polish audio course at the moment. I don't know Polish, but I am learning as I am going along since everything is explained on the CD. I came across the Polish word kilkanaście which is made up of kilka, which means 'a few' and naście, which is the 'teen' bit of the numbers 13-19. So, the word means an approximate figure, somewhere between 13 and 19. I translated it in the glossary as 'a dozen or so', but I found it interesting that there is no equivalent in English for that sort of quantity. There are words for unspecified amounts eg a handful, several, but they can mean any number, depending on what is the norm. If someone has a handful of friends, it might be just two or three, but a handful of people in the country might be a few thousand.