There aren't any common abbreviations for the word "monkey". It's already a relatively short word, and there's no need to shorten it further.
However, if you're interested in abbreviations related to monkeys, you might be looking for things like:
* Primate: A general term for monkeys, apes, and other related animals.
* Simian: Another term for monkeys and apes.
Let me know if you have any other questions!