is 'IS" friday the 13th, don't'cha' know
friggatriskaidekaphobia or paraskevidekatriaphobia for our Greek mastering brethren.
"The actual origin of the superstition, though, appears also to be a tale in Norse mythology. Friday is named for Frigga, the free-spirited goddess of love and fertility. When Norse and Germanic tribes converted to Christianity, Frigga was banished in shame to a mountaintop and labeled a witch. It was believed that every Friday, the spiteful goddess convened a meeting with eleven other witches, plus the devil — a gathering of thirteen — and plotted ill turns of fate for the coming week. For many centuries in Scandinavia, Friday was known as "Witches' Sabbath."
... pretty funny our modern culture has taken a turn to phrases like 'TGIF" (thank god it's friday) .. or maybe it's not so funny...