There is no such thing as “creating meaning”. Either your product is meaningful, then there is already a community out there that just needs to be identified and nurtured, or it isn’t, which is rarely the case.
The nurturing part is always the hardest. You have to be 100% aware of the fact that a community in general consists of less than 10% information contributors and more than 90% information consumers. Now, the 90% are there for the information, but what are the 10% there for?
Fame, love, incentives, meaning, being someone, their own self importance.
You have to nurture the 10% to build a community and making it last. How do you cater to them? Through feedback.
Take a good look at Quora, which does an excellent job at making the people who answer questions feel happy about that and come back. The key words here are game mechanics and social fame. To put it briefly: enable the 90% to give as much feedback (likes, votes etc.) to the 10% as they can. Encourage them to. Then channel and distribute that feedback to the 10% in a way that lets them embrace their role as the information provider and makes them feel proud about their work and share that experience.
See the answer on Quora: