a gay blade
What is the origin of the phrase "As gay as a blade"?
A gay blade originally refered to a dashing swordsman whose sword was often upright and at the ready. Later it was applied to any gallant young man.
In modern times, the change of meaning of the word gay and the movie "Zorro: The Gay Blade" (in which the famous swordsman has a homosexual twin brother) have greatly influenced/changed the meaning of the phrase.
In dog show parlance, a gay tail is one that is upright and sometimes curving over the back not unlike an upright sword (though I don't know for sure that the two meanings are related).