"Isonomic" is an adjective that describes something that is equal or consistent in terms of its laws or principles. So, if you want to express the same meaning using different words, here are some synonyms that may be useful: equitable, fair, just, even-handed, impartial, unprejudiced, unbiased, objective, consistent, systematic, symmetrical, balanced, proportional, harmony, and conformity. Each of these words has a slightly different connotation, but all carry the idea of something that is just and balanced, without favoritism or inconsistency. Using these alternative words can add variety and nuance to your writing while conveying the same core meaning.