There is nothing wrong with circularity in dictionaries, though. This is a solution in search of a problem.
It may be the case that the definition A happens to use some word B, in whose definition we find word C, whose definition uses A. However, that isn't really a problem, because these definitions are not simply substitutions of exactly one word for another. The definition of A uses numerous other words other than B, that of B uses words in addition to C, and C uses words in addition to A.
That is, the existence of cycles in definitions doesn't necessarily make the definitions irresolvably circular.
It may be the case that the definition A happens to use some word B, in whose definition we find word C, whose definition uses A. However, that isn't really a problem, because these definitions are not simply substitutions of exactly one word for another. The definition of A uses numerous other words other than B, that of B uses words in addition to C, and C uses words in addition to A.
That is, the existence of cycles in definitions doesn't necessarily make the definitions irresolvably circular.