OP wasn’t hard, but what in the world does WAG mean. I’ve seen it in context several times, but I still can’t get a handle on it. It seems to be used in place of What I’d Guess, but that makes WIG. Help.
Wild Ass Guess
Fighting ignorance since 10:30
If you are in science or engineeering, the term is SWAG for Scientific Wild Assed Guess.
This means you have discovered some numbers, say 1° falling temperatures in Greenland, and a reporter insists you tell the “meaning” of the data or he can’t report it and give you credit.
So you say “The next ice age is 10,000 years off, give or take 100,000 years”
Some useful links for acronyms:
And remember… there’s no such thing as a stupid question, unless it deals with the word “gry”.
If there’s no such thing as a stupid question, how do stupid people ask their questions? 
Like I do…