social hub 

(noun) A person who is the connection between networks of many different individuals and groups.

Mira has so many different groups of friends, she's such a social hub!

social hub by Mira Bethy March 5, 2017

social network hub 

An individual that is so important to a social network that they consistantly check landline voice mail, text message and send email to their social network at the same time!

Bobby: I went to see Nadine about some work, but she was very busy. She appeared to be talking on the phone and texting at the same time!
Mike: She is the social network hub of her apartment complex so you may be able to catch her tomorrow with work issues!

social network hub by TopHud February 6, 2008