gematria
A cabalistic method of interpreting Hebrew words, based on numerical values of letters.
countable, uncountable
Suppose a secret force of Jesuits, receives each Day a summary of Observations made at Greenwich, and transcalculates it according to a system known to the Kabbalists of the Second Century as Gematria, whereby Messages may be extracted from lines of Text sacred and otherwise, a Knowledge preserv’d by various Custodians over the centuries, and since the Last, possess’d by Jesuit and Freemason alike.
Where it comes from
From Aramaic גִּימַטְרְיָא (gīmāṭrəyā), from Ancient Greek γεωμετρία (geōmetría, “geometry”). Doublet of geometry.
Adapted from the Wiktionary entry gematria (CC BY-SA 4.0).