Fusogens are proteins that play a critical role in membrane fusion, which is a key component of various physiological processes in cells like fertilization and neurotransmitter release. There are several synonyms for the word "fusogen," and some of them include membrane fusion proteins, virally induced membrane fusion proteins, fusogenic proteins, and fusion peptides. The use of these synonyms is crucial in the analysis of various cellular functions that require the involvement of fusogens. These terms help researchers to identify and describe specific proteins that participate in membrane fusion and their specific roles in different biological processes. The study of fusogens and their synonyms is essential in understanding critical cellular activities and the development of therapeutic strategies for diseases where membrane fusion is impaired.