Quidnunc: (n) a gossiper or inquisitive person.
In a sentence:
Director of sales and marketing: Why is Mr Smith, our most important client, being led out of the hotel by the police?
General manager: Well, according to our resident quidnunc, the concierge, Mr Smith had a bit of a party last night in his suite.
DOSM: Well that is nothing new, what was the problem?
General manager: Unfortunately there was break in at the zoo last night. According to the concierge, the police followed a trail of rhino and giraffe dung back to our hotel and into Mr Smith’s suite.
DOSM: Oh dear, are the animals okay?
General manager: The animals are, but the suite isn’t.
DOSM: I thought I saw Mr Smith’s wife leaving the hotel in a hurry this morning – she was only wearing her nightie.
General manager: That wasn’t Mrs Smith, that was a hippo who had riffled through their luggage and escaped out of the hotel.