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Martes 13

Definition of Martes 13

In Spanish-speaking countries, instead of Friday, Tuesday the 13th is considered an unlucky day.


  1. Unlucky day
  2. Friday the 13th

ORIGIN OF Martes 13

Although Friday is traditionally considered a day to be wary of, Spaniards view Tuesday with much more suspicion.

The exact origins of the fear of either day remain unclear, but several theories have been proposed. First, Tuesdays were considered to be dominated by the influence of Mars, the god of war, since etymologically “Tuesday” comes from his name.

The superstition is also reinforced by historical events such as the fall of Constantinople to the Fourth Crusade on Tuesday, April 13, 1204 and its fall to the Ottomans on Tuesday, May 29, 1453.

There is even a proverb that says “on Tuesday neither marry nor embark nor depart from home”. Which refers to the fact that on Tuesdays you should not get married, get on a ship or leave your home.

The western world usually considers that the number 13 brings bad luck, to the point that hotels usually omit it in the rooms.


The Greeks also consider Tuesday (and especially the 13th) an unlucky day. Tuesday is considered to be dominated by the influence of Ares, the god of war (or Mars, the Roman equivalent).

In Italian popular culture, Friday the 17th is considered an unlucky day. The origin of this belief could be traced back to the writing of the number 17, in Roman numerals: XVII. Shuffling the digits of the number easily yields the word VIXI ‘I have lived’, which implies death in actuality, a harbinger of bad luck.