Abjad numerals in the context of "Nun (letter)"

In numerology, isopsephy (stressed on the I and the E; from Greek ἴσος (ísos) 'equal' and ψῆφος (psêphos) 'count', lit. 'pebble') or isopsephism is the practice of adding up the number values of the letters in a word to form a single number. The total number is then used as a metaphorical bridge to other words evaluating the equal number, which satisfies isos or "equal" in the term. Ancient Greeks used counting boards for numerical calculation and accounting, with a counter generically called psephos ('pebble'), analogous to the Latin word calculus, from which the English calculate is derived.

Isopsephy is related to gematria: the same practice using the Hebrew alphabet. It is also related to the ancient number systems of many other peoples (for the Arabic alphabet version, see Abjad numerals). A gematria of Latin script languages was also popular in Europe from the Middle Ages to the Renaissance, and its legacy remains an influence in code-breaking and numerology.

In numerology, gematria (/ɡəˈmeɪtriə/; Hebrew: גמטריא or גימטריה, gimatriyyā, plural גמטראות or גימטריות, gimatriyyot, borrowed via Aramaic from Koine Greek: γραμμάτια) is the practice of assigning a numerical value to a name, word, or phrase by reading it as a number, or sometimes by using an alphanumeric cipher. The letters of the alphabets involved have standard numerical values, but a word can yield several values if a cipher is used.

According to Aristotle (384–322 BCE), isopsephy, based on the Greek numerals developed in the city of Miletus in Anatolia, was part of the Pythagoreanism, which originated in the 6th century BCE. The first evidence of use of Hebrew letters as numbers dates to 78 BCE; gematria is still used in Jewish culture. Similar systems have been used in other languages and cultures, derived from or inspired by either Greek isopsephy or Hebrew gematria, and include Arabic abjad numerals and English gematria.

Ḍād (ﺽ) is the fifteenth letter of the Arabic alphabet, one of the six letters not in the twenty-two akin to the Phoenician alphabet (the others being ṯāʾ, ḫāʾ, ḏāl, ẓāʾ, ġayn). In name and shape, it is a variant of ṣād. Its numerical value is 800 (see Abjad numerals). It is related to the Ancient North Arabian 𐪓‎‎‎, South Arabian 𐩳.

The letter symbol itself is a derivation, by addition of a diacritic dot, from ص ṣād (representing /sˤ/).

Che or cheem (چ‎) is a letter of the Persian alphabet, used to represent [t͡ʃ]. The letter derives from Jīm (ج‎) by the addition of two dots. It is found with this value in other Arabic-derived scripts. It is used in Persian, Urdu, Pashto, Kurdish, Uyghur, Kashmiri, Azerbaijani, Ottoman Turkish, Malay (Jawi), Javanese (Pegon), and other Indo-Iranian languages. It is also one of the five letters the Persian alphabet added to the Arabic script (the others being ژ, پ, and گ in addition to the obsolete ڤ. Its numerical value is 3000 (see Abjad numerals).

Gaf (Persian: گاف; gāf), is the name of different Perso-Arabic letters, all representing /ɡ/. They are all derived from the letter kāf, with additional diacritics, such as dots and lines. In name and shape, it is a variant of kaf. It is also one of the five letters the Persian alphabet added to the Arabic alphabet (the others being ژ, پ, and چ in addition to the obsolete ڤ). Its numerical value is 5000 (see Abjad numerals). There are four forms, each used in different alphabets:

• گ‎ in the Persian alphabet, Tausug written in Arabic Script
• ݢ‎ in the Jawi script
• ࢴ/ڮ‎ in the Pegon script
• ګ‎ in Pashto

Ayin (also ayn or ain; transliterated ⟨ʿ ⟩) is the sixteenth letter of the Semitic scripts, including Phoenician ʿayin 𐤏, Hebrew ʿayin ע‎, Aramaic ʿē 𐡏, Syriac ʿē ܥ, and Arabic ʿayn ع‎ (where it is sixteenth in abjadi order only). It is related to the Ancient North Arabian 𐪒‎‎, South Arabian 𐩲, and Ge'ez ዐ.

The letter represents a voiced pharyngeal fricative (/ʕ/) or a similarly articulated consonant. In some Semitic languages and dialects, the phonetic value of the letter has changed, or the phoneme has been lost altogether. In the revived Modern Hebrew it is reduced to a glottal stop or is omitted entirely, in part due to Ashkenazi European influence and their difficulty in pronouncing the consonant.