What is merchant banking?

According to Google:

Definitions of Merchant Banking on the Web:

Merchant banks offer consultancy services for mergers and acquisitions and financial restructurings, and the associated financing (raising the necessary funds).
www.belgolaise.com/en/glossaire/

Merchant banks are banks that specialize in activities that facilitate trade and commerce. This typically involves international finance (because of their size and complexity), long term loans to companies, and underwriting. Merchant banks do not offer usual banking services to the general public.
Merchant bank - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Merchant_Banking)

Merchant banking refers to investment by a bank in a non-financial business. It is virtually equivalent to private equity investing.
Merchant bank - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Merchant_banking)