In modern numerological terminology, arithmancy (a shortened form of Greek ἀριθμομαντεία divination by numbers) is a form of divination based on assigning numerical value to a word or phrase, by means of a simplified version of ancient Greek isopsephy or Hebrew/Aramaic gematria, as adapted to the Latin alphabet. Arithmancy is associa...
divination using numbers
• (n.) Divination by means of numbers.
Ar'ith·man`cy noun [ Greek ... number + -mancy .] Divination by means of numbers. 
Arithmancy is divination by numbers.
arithmancy, arithmomancy, arithomancy Divination with numbers, numerology; practiced by Greeks and Chaldeans. The Greeks would analyze the names of warring enemies and determine their numerical values and from this they would predict the result of the battle. The Chaldeans divided their alphabet into three sections of seven letters and made a sym...
noun divination by means of numbers
divination by the use of numbers, esp. by the number of letters in names.