ˈbolt-on BrE AmE adjective especially British English
bolt-on part/component/extra something that is connected to the outside of a machine after it has been made, and is then part of the machine
ˈbolt-on BrE AmE adjective especially British English
bolt-on part/component/extra something that is connected to the outside of a machine after it has been made, and is then part of the machine
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012