Hybrid integrated circuit is a term that refers to a type of circuit that combines both analog and digital components on a single chip. This type of circuit is often used in electronics and communications systems, where compactness and integration are critical. There are several synonyms for hybrid integrated circuit, including chip-on-board (COB), chip-on-chip (COC), multi-chip module (MCM), and system-on-chip (SoC). Each of these terms refers to a unique type of circuit design that combines different components into a single package. So, depending on the context, any of these synonyms could be used to refer to a hybrid integrated circuit.