Also, "loose" can be used as a verb meaning "release." The most famous example I can think of is from The Battle Hymn of the Republic "He hath loosed the fateful lightning of His terrible swift sword."

Also, the word "looser," the comparative form of the adjective "loose," is a real word, so it is not flagged by spell-checkers. The idiocy and sloth of people that use "looser" when they mean "loser" is that they believe that if their writing passes the spell-check, it must be correct. They could knot bee moor rong*!

* a synonym for rung (of a ladder).