This is a general name referring primarily to Point of Sale System that issue invoices/receipts. The terminal can run on windows, linux, android, MacOs or any platform.
Here are some examples of POS System;
A computer running any system that issues invoices/receipts is considered a terminal.
Note that with the new Electronic Invoicing System, receipts can be printed or sent electronically as long as they contain a QRCode that can be scanned for validation.
POS System connected to MRA is a terminal.
Hand held portable android POS is a terminal
Terminal can also refer to any system connected to MRA to report sales. These can be ERP systems, Electricity Token systems, Water Token system etc
Terminals do not necessarily have to be a physical device. A client application being developed from an IDE is also considered as a terminal.
Technically, any client application connecting to MRA EIS API os considered a terminal.