It kinda does, it means it's an actual financial security that is backed by something tangible like the assets, profits, or revenue of the company, and which offer legal rights such as revenue distribution. In the case of NEX token it means that holders of the token can legally expect their share of up to 75% of exchange revenue. NEX token is subject to laws that govern securities, and protect investors on some level. The company can still fail and investors lose their money, but the founders can't just scam people outright, not unless they want to go to jail. With a utility token investors don't have any rights and project founders don't have any legal obligations, they can scam any second and do so all the time without punishment.

https://medium.com/nashsocial/security-tokens-3fcd6b1a2b13

"Our issuing of a security token brings Nash investors many benefits, such as protection against market manipulation, fraud and insider trading. Perhaps most importantly, it allows us to pay our investors dividends through fees taken by the exchange, a form of profit-sharing."