The letter Zayin is the seventh letter in the Hebrew alphabet, and it appears in a number of other Semitic language’s alphabets. By way of the ancient Phoenician language, the letter Zayin eventually entered the Greek and Latin alphabets, becoming the letters Zeta and Z, respectively, although its place in the different alphabets changed. The original meaning of the letter Zayin is a "sword" or "sharp weapon", with the word "lezayen" coming to mean "to be armed" in the Modern Hebrew language.
The root meaning of the Hebrew letter Zayin is interesting in itself. While it means a "sword "or "sharp weapon", as explained above, the meaning of the word is also connected to food and sustainance. For example, the Modern Hebrew word "mazon" (מזון), meaning "food" or "sustainance", and the Modern Hebrew word "hazana" (הזנה), meaning "nourishment", both come from the same root as Zayin. Some scholars say that the meaning behind this is that while pointless bloodshed is certainly not the ideal, we sometimes must fight in order to defend our lives and our way of life.
Just as its literal meaning is complex, the spiritual meaning of the Hebrew letter Zayin is significant, as well. The letter has the numerical value of seven, which has much significance, including the fact that the Sabbath is the seventh and holiest day of the week, and according to Biblical law, the land is meant to lie fallow every seventh year according to a law called "shmita". As Ziyan is the first letter of the word "zahor" (זכור), meaning to remember, and this is one of two basic commandments of the Sabbath, there seems to be a very strong link between the seventh letter in the Hebrew alphabet and the day of rest!