peripheral
adjective
uk/pəˈrɪfərəl/ usused to describe something that is not as important as the main thing to which it is related, for example a company's less successful activities in relation to its most successful ones:
Some of the more peripheral interests have been sold and the company now has a clearer focus on certain markets.
IT
used to describe a piece of equipment, such as a printer, that can be connected to a computer:
The system is expected to boost sales of PCs as well as components, applications, and peripheral devices.
peripheral
noun [ C ]
uk/pəˈrɪfərəl/ us IT
a piece of equipment, such as a printer, that can be connected to a computer:
Whether something is a peripheral or part of a computer is not always clear.