1. An example of bad nomenclature or terminology; especially, in biology and botany: When the editor had the new botany text proofread, she discovered many examples of caconyms which had to be corrected before publication.
2. A name, especially a taxonomic name, that is considered linguistically undesirable or bad: When correcting Tomas' essay on biological terms, the instructor was amused by some of the caconyms which he used and which needed to be corrected because they were not relevant to the context of the subject.