When it comes to finding synonyms for the phrase "hatch up," there are several words and phrases that can be used interchangeably. Some common synonyms include "concoct," "devise," "fabricate," "invent," "cook up" and "scheme." All of these words essentially describe someone or something that is inventing or creating a plan or idea. Other synonyms for "hatch up" might include "dream up," "plot," "craft," "conceive," "formulate," "orchestrate" or "design." No matter which word or phrase you choose to use, the basic idea behind "hatching up" something is always the same - to create or come up with something new or inventive.