Offshore Software R&D is the provision of software development services by a supplier (whether external or internal) located in a different country from the one where the software will be used. The main reason behind companies using offshore software development services is the higher development cost of the local service providers. The global software R&D services market, as contrasted to ITO and BPO, is rather young and currently is at a relatively early stage of development.[1]

offshore", it means overseas. So if you avail of offshore software outsourcing, you are outsourcing software development to a different country. When you say onshore software outsourcing, it is still outsourcing but the company you outsourced the software development is within your country.

It usually refers to development taking place in another country.