Dictionaries don’t. They even give opposing definitions. 

 

If you ask random people (I’ve asked investment bankers),
they might say it’s about setting up subsidiaries in foreign countries.
 

An expert in foreign languages will say it’s a language service. 

An agency that buys their services will tell you it’s an entire industry. 

A corporate strategy professor who teaches localisation and can tell what an industry is will laugh at them. (Mine did.) 

​

But it can also be about supply chains, data centres, and functions of the brain. (Brain localisation is not exactly my domain, but does anybody need a management consultant for that?)