Without a link or information about the dictionary itself, this is hard to answer.
I would say it is one of a few things:
Very basic protection - it simply detects if it is being run from a flash drive - try copying to another one.
Better protection - It detects the USB/Device ID - Try getting an identical drive.
Advanced protection - It has some sort of on board crypto/protection chip - Emulation or (easier) hacking the actual program is your best bet.
In any of these, it is worth saying that if they prevent you from doing it, it means they do not want you to and you are most likely breaking the EULA and I would not recommend doing it.