The inscription is found on fonts in many churches in Western Europe: Orléans (St.

Nipson anomēmata mē monan opsin palindrome, on a font at St Martin, Ludgateīyzantine baptismal fonts were often inscribed with the 4th-century Greek palindrome, ΝΙΨΟΝ ΑΝΟΜΗΜΑΤΑ (or ΑΝΟΜΗΜΑ) ΜΗ ΜΟΝΑΝ ΟΨΙΝ (" Nipson anomēmata mē monan opsin") 'Wash sin(s), not only face', attributed to Gregory of Nazianzus most notably in the basilica of Hagia Sophia in Constantinople. Indeed, composing palindromes was "a pastime of Roman landed gentry". Other palindromes found at Pompeii include "Roma-Olina-Milo-Amor", which is also written as an acrostic square. Hence, it can be arranged into a word square that reads in four different ways: horizontally or vertically from either top left to bottom right or bottom right to top left. It is also an acrostic where the first letters of each word form the first word, the second letters form the second word, and so forth. This palindrome, known as the Sator Square, consists of a sentence written in Latin: sator arepo tenet opera rotas 'The sower Arepo holds with effort the wheels'. Ī 1st-century Latin palindrome was found as a graffito at Pompeii. The ancient Greek poet Sotades (3rd-century BC) invented a form of Ionic meter called Sotadic or Sotadean verse, which is sometimes said to have been palindromic, since it is sometimes possible to make a sotadean line by reversing a dactylic hexameter. Historical development Ī Sator square (in SATOR-form), on a wall in the medieval fortress town of Oppède-le-Vieux, France crab-like) to refer to letter-by-letter reversible writing. It is derived from the Greek roots πάλιν 'again' and δρóμος 'way, direction' a different word is used in Greek, καρκινικός 'carcinic' (lit. The word palindrome was introduced by English poet and writer Henry Peacham in 1638. In automata theory, the set of all palindromes over an alphabet is a context-free language, but it is not regular. Palindromes are also found in music (the table canon and crab canon) and biological structures (most genomes include palindromic gene sequences).

The concept of a palindrome can be dated to the 3rd-century BCE, although no examples survive the first physical examples can be dated to the 1st-century CE with the Latin acrostic word square, the Sator Square (contains both word and sentence palindromes), and the 4th-century Greek Byzantine sentence palindrome nipson anomemata me monan opsin. The 19-letter Finnish word saippuakivikauppias (a soapstone vendor), is the longest single-word palindrome in everyday use, while the 12-letter term tattarrattat (from James Joyce in Ulysses) is the longest in English. In essence, “ mirror writing” on vehicles are used to quickly catch the attention of other motorists.The 4th-century Greek palindrome: ΝΙΨΟΝ ΑΝΟΜΗΜΑΤΑ ΜΗ ΜΟΝΑΝ ΟΨΙΝ ( Wash your sins, not only your face), at the Hagia Sophia in Constantinople.Ī palindrome is a word, number, phrase, or other sequence of symbols that reads the same backwards as forwards, such as madam or racecar, the date and time 12/21/33 12:21, and the sentence: "A man, a plan, a canal – Panama". In some countries, the words “police” and “paramedics” are spelled backwards for similar reason. International standards state that ambulances should have the world ambulance written in reverse on the bonnet. This is necessary because in traffic, ambulances are supposed to be given right of way and so apart from their sirens the word ambulance is made easily readable from the mirror of vehicles in front of them. That way, those cars that need to give way for the ambulance to drive through in traffic would do so. This makes the ambulance front visible in the rear-view mirrors of other cars. That way, people looking in their rearview mirrors or side-mirrors can read it as AMBULANCE.Īmbulance are typically in greater speed than surrounding vehicles. The word is written backwards on the front of the vehicles to enable motorists in front to easily read it on their rear-view mirrors, especially during emergencies.