My guess, as a Blazers fan, is that it has to do with the Oregon Trail, and Portland being one of the ending points of said trail...but I'm not a pro.
I've read that it has to do with the pioneering history of oregonians...and the name 'pioneers' was taken by a local college team already, so a citizen vote deemed the 'trail blazers' the winning choice.
Portland Trail Blazers was created in 1970.
Paul Allen is the owner of the Portland Trail Blazers
Will Barton is number 5 on the Portland Trail Blazers.
1976
Damian Lillard is number 0 on the Portland Trail Blazers.
Allen Crabbe is number 23 on the Portland Trail Blazers.
C.J. McCollum is number 3 on the Portland Trail Blazers.
Earl Watson is number 17 on the Portland Trail Blazers.
Joel Freeland is number 19 on the Portland Trail Blazers.
LaMarcus Aldridge is number 12 on the Portland Trail Blazers.
Meyers Leonard is number 11 on the Portland Trail Blazers.
Mo Williams is number 25 on the Portland Trail Blazers.