FASCINATING, WONDERFUL! This really is a kick. Yes, language can be construed wrongly because of the vernacular changing from location to location. I had a friend, who when down, was told by a Brit to "keep your pecker up". Of course, she was referring to her chin, not male anatomy. The kicker of the whole situation was that the friend who was down went by the nickname "Muff". Go figure. I'm sitting here chuckling as I write...

Seeing all the definitions of gig, I think probably the answer to the question of it's origin as a musician's job is more mundane and unexciting and not so mysterious. If Garg's dictionary is somewhere correct about the date of it's usage that way, then I would guess it started as some colloquial expression and spread. Look at the way our new gadgets and phenomenae get named and how fast, because of technology, the expressions are adopted by whole countries.

Margo