Here are some possible scenarios:
* Misspelling: You might be thinking of a term like "bishoping." Bishoping is an unethical practice where a horse's teeth are artificially filed down to make them appear younger than they are. This is often done to deceive buyers.
* Regional term: There might be a local slang term for a particular horse-related condition or practice that is referred to as "bishopping." If you can provide more context about where you heard this term, I might be able to help you identify it.
* Misunderstanding: You might be misunderstanding a term related to horses. If you can provide more details about what you think "bishopping" refers to, I can try to clarify.
Please clarify what you are asking about, and I will do my best to assist you.