GREGORIAN a.
Pertaining to, or originated by, some person named Gregory, especially one of the popes of that name. Gregorian calendar, the calendar as reformed by Pope Gregory XIII. in 1582, including the method of adjusting the leap years so as to harmonize the civil year with the solar, and also the regulation of the time of East…
HEPTAGONAL a.
Having seven angles or sides. Heptagonal numbers (Arith.), the numbers of the series 1, 7, 18, 34, 55, etc., being figurate numbers formed by adding successively the terms of the arithmetical series 1, 6, 11, 16, 21, etc.