Word History: The word abracadabra is first attested in a poem about medical matters attributed to the Roman author Quintus Serenus Sammonicus, who lived around the second century AD. In one of the poem's prescriptions for magical cures, the letters of the word abracadabra are written on papyrus in an inverted triangle and worn as an amulet around the neck. The top line of letters in the triangle consists of the word abracadabra, and one letter is subtracted from the end of this word in each line below it: abracadabr, abracadab, abracada, and so forth. At last only the letter a remains to form the vertex of the triangle. As the letters disappear, so supposedly does the disease or trouble.