заказчик означает в английский

client [clients]▼(a customer or receiver of services)
noun
[UK: ˈklaɪənt] [US: ˈklaɪənt]

customer [customers]▼(one who purchases or receives a product or service)
noun
[UK: ˈkʌ.stə.mə(r)] [US: ˈkʌ.stə.mər]