This is a very old word with a relatively modern meaning. It comes from the Old English godsibb, meaning a godparent or baptismal sponsor. It is a compound of god + sib (meaning blood relation as in sibling). From Wulfstan’s 1014 Sermo Lupi ad Anglos:

Godsibbas and godbearn to fela man forspilde wide þynd þas þeode.
(Gossips and godchildren to many of those destroyed far and wide while they thrived.)

By the 14th century, the term was being used to mean a close friend, one you might chose to be godparent to your children. It was applied to both men and women, although in later uses it came to be applied only to women. From William Langland’s 1362 The Vision of William Concerning Piers Plowman:

“Ic haue good ale, gossib,” quod heo. “Gloten, woltou asaye?”
("I have good ale, gossip,” they said. “Glutton, wouldn’t you call it?")

By the mid-16th century, gossip was being used to mean a flighty woman, one who would engage in idle talk. From Thomas Drant’s 1566 A Medicinable Morall, That Is The Two Bookes of Horace His Satyres Englished:

Full gosseplike, the father sage beginnes his fable then.

From there it came to mean the idle talk itself. From Sporting Magazine of 1811:

I was up to his gossip, so I took him.

And from Washington Irving’s Sketch Book of 1820:

A kind of travelling [sic] gazette, carrying the whole budget of local gossip from house to house.

(Source: Oxford English Dictionary, 2nd Edition)

Powered by ExpressionEngine
Copyright 1997-2014, by David Wilton