n (telecommunications) Any device that directs packets of information using OSI layer 3 (network layer) information.
n (Internet) A device that connects LAN | local area networks to form a larger internet by, at minimum, selectively passing those datagrams having a destination IP address to the network which is able to deliver them to their destination; a network gateway.
n (electronics|electronic design automation) In integrated circuit or printed circuit board design, an algorithm for adding all wires needed to properly connect all of the placed components while obeying all design rules.