Grammar Girl Mignon Fogarty asks, "Why doesn’t 'Veterans Day' have an apostrophe?"
Ah, the apostrophe. Humble and omnipresent punctuation mark, misused everywhere.
Your usage for this weekend's holiday could be "Veterans' Day" (quite rare), but not "Veteran's Day" (incorrect)
In using 'Veterans Day', the Grammar Girl says, "Veterans" is acting like an adjective, telling you what kind of day it is (just as "tree" in "tree farm" tells you what kind of farm it is).
If you are using that apostrophe-s at the end — Veteran's Day — "Veteran" is being made possessive, so it's the day of celebration for just one veteran. It's not just one veteran, of course.
I am one such veteran, serving in the Army 1976-79. My three years earned me about $500 a month for four years of college afterward. In 1979, University of Texas tuition was only one third of that amount. I could live in the $125 shotgun apartment and fill the cupboards with pasta and survive on grocery store pizza. While at that school, working toward my journalism degree, I learned and practiced the careful use of the apostrophe.
Thank the veterans in your life this weekend (we love hearing "Thank you for your service.") Serve up your apostrophes well, too.