Alternative form of etc.

(finance) Acronym of Exchange-Traded Commodity. / (wireless location) Acronym of Electronic Toll Collection (system to eliminate delays on toll roads by collecting them electronically)

Initialism of electronic toll collection system.

(railways, transport) Initialism of European Train Control System (a signalling, control and train protection system, especially for high-speed lines.)

And so on: used to note that the rest of a list or piece of information has been left out on the assumption that it is similar or already known.