Hi,
Routed link means layer 3 physical interface where we can assign an ip address. The interface on routers on which we can assign an ip address are router interface.
Even on layer 3 switches like 3550 if you convert switch port into layer 3 port with a command "no switchport" it will be routed interface or routed link if something is connected to that interface.
Hope this helps.
Ankur
