Chronogram
Chronogram , noun
[Greek {not transcribed} time + {not transcribed} writing, character: compare French chronogramme.]
1.
An inscription in which certain numeral letters, made to appear specially conspicuous, on being added together, express a particular date or epoch, as in the motto of a medal struck by Gustavus Adolphus in 1632: ChrIstVs DVX; ergo trIVMphVs. - the capitals of which give, when added as numerals, the sum 1632.
2.
The record or inscription made by a chronograph.