Dual board is a term commonly used to refer to a type of motherboard with two CPU sockets, which allows for increased processing power. However, there are several synonyms that can be used to describe this type of motherboard. One commonly used term is "dual CPU motherboard" which directly indicates the presence of two CPU sockets. Another term is "multi-socket motherboard" which can include motherboards with more than two CPU sockets. Additionally, "multiprocessor motherboard" or "server motherboard" can also be used to describe motherboards with dual sockets, as they are often used in high-end servers and workstations that require powerful processing capabilities.