-a person who is eager to know the latest news and gossip; a gossip or busybody.
Etymology is pretty straightforward; "gossip-monger," 1709, formed from L. quid "what" and nunc "now," to describe someone forever asking "What's the news?"
Usage:
I chose this word so I could share this amusing and true tidbit.
When he was a child, my husband lived down the street from a renown quidnunc named Mr. Parker. It was many years before he realized that Nosy Parker wasn't just a nickname bestowed on this gentleman by his neighbors.