What does the name Jig mean in "Hills Like White Elephants" and why does he call her that?

The jig
is a dance in Ireland. Giving the girl the nickname of Jig may suggest that she is from Ireland
and that she is, or has been, a lively, spirited girl, since the jig is an extremely lively
dance. The girl may have performed this dance on more than one occasion during their travels.
They have been together a long time. This is shown by all the hotel stickers on their
luggage--possibly also indicated by the fact that they are carrying so much luggage. Jig is
obviously an affectionate nickname. Hemingway is writing this story from an strictly objective
perspective. That is why he doesn't give his characters names. The reader only knows what he can
see, hear, and deduce from what he sees and hears. The nickname Jig may suggest the girl is
Irish. She has to be from someplace, and evidently she is not from America. She speaks good
English, so she would have to be frp, England, Scotland, Wales, Ireland, Canada, Australia or
New Zealand--most likely from the European places since the American must have met her in
European.