The term "proembryo" is commonly used in the field of botany and plant science to refer to the early stage of development of a plant embryo. However, there are several other synonyms that can be used to describe this particular developmental stage. Some of the synonyms for proembryo include the terms "morula," "globular embryo," and "pre-globular embryo." Each of these terms describes embryonic development during different stages, with the morula stage referring specifically to the stage before the embryo forms a blastula, while the globular and pre-globular stages refer to the early stages of development after the blastula has formed.