motherboard Syllabification: (moth·er·board)Pronunciation: /ˈməT͟Hərˌbôrd/Translate motherboard | into French | into German | into Italian Definition of motherboard noun Computing a printed circuit board containing the principal components of a computer or other device, with connectors into which other circuit boards can be slotted. motherboard in other Oxford dictionaries Definition of motherboard in the British & World English dictionary