Taco Tuesdays, or Tuesday as it’s known around town, are unofficial holy days in Houston, but the dynamics of the phrase may surprise you.

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Trademarked to Wyoming-based taco staple Taco John’s, the catchy term is off limits for taco spots in 49 states to use during their regular course of business.

According to a franchise legend dating back to the early ‘80s, a store owner in Minnesota first coined his slowest day of the week “Taco Twosday” in an attempt to boost sales. Taco John’s knew a good thing when they saw it and trademarked the term in 1989.

Ever since, Taco John’s has been persistent in defending its alliterative axiom, unafraid to send cease and desist letters at first sign of taco twofer almost everywhere in the U.S. New Jersey was the only state with a taco team to beat the chain to the U.S. Patent and Trademark Office for rights in the Garden State.

Under applicable law, common words may be trademarked when they’re used for a specific purpose, as opposed to purely descriptive terms, like “World’s Best,” and it is up to grantees of trademarks to do their own policing of the registered expression

Lax defense of trademarks that once existed for Kleenex and Xerox are why the terms are no longer protected and currently part of the public domain. As one attorney described it, too keep a trademark, the general population needs to think of the single company associated with a trademark, not just the plain tissue or photocopies that come to mind for the two examples mentioned above.

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It’s unlikely Taco John’s comes to mind when Houstonians hear Taco Tuesday, however, probably because none of its 400 locations are in Texas.

In related taco news, over 73,000 pounds of Texas beef were recalled this week due to E. coli concerns.

Maybe we should skip the beef this week – in our tacos and regarding the Tuesday special name.

Taco Tuesday for all!

The history of Taco Tuesday is food for thought and a story you’ll want to bring to the table tonight AP Photo/Marco Ugarte