Feeling rather bogeyed, I'm looking for some fore-closure to this query — help!
Most interesting. I lways knew it was a traditional warning cry while golfing, but I just googled it and there is sever possible sources
[Cut paste and some editing from WIKIPEDIA]
It is mentioned as early as 1881. The term means "look ahead", and it is believed to come from the military "beware before", which was shouted when a battery fired behind friendly troops. - This one sounds most likely to me - it just fits with the Scots and the British history as I know it.
Other possible origins include the term being derived from the term "fore-caddy", a caddy waiting down range from the golfer to find where the ball lands.
It also may have a contraction of the Gaelic cry Faugh a Ballach! (i.e. Clear the way!) which is still associated with the sport of road bowling which has features reminiscent of golf.
=When I get to work I'll try to look it up in the OED and see when it was first used in written form.
"Fore" in this sense is the same as in a book's "foreword," i.e., "that which goes before." Or even, the 'fore' in "before." Means "those in the fore should look out - here comes a shot."