Like a coin, the Great Seal has two sides: the obverse (front) and the reverse (back). Images of both sides have appeared by law on U.S. currency since 1935.
The mottos on the reverse of the Seal are both taken from the works of the Latin poet Virgil.
Annuit coeptis: literally, “favors the undertaking”; If the eye above the pyramid stands for the eye of Providence, annuit coeptis can be translated as “He/God favors the undertaking.”
Jupiter omnipotens, audacibus adnue coeptis. –Aeneid,book IX, line 625.
Ascanius, the son of Aeneas, is praying to Jupiter, asking him to grant him success in his undertakings.
Novus ordo seclorum: literally, “new order of the ages.”
Many people who are familiar with the word secular, but not with classical Latin, assume that the motto means “the new secular order,” i.e., “not religious.” Seclorum, however, comes from the Latin word saecla, meaning “generation, century,” or “age”.
The quotation comes from Virgil’s Fourth Eclogue:
Magnus ab integro saeclorum nascitur ordo. Roughly, “a great order of the ages has been freshly born.”
The line is part of a prophecy that proclaims the birth of a new (fresh) order of the ages. Virgil was big on flattering the Emperor Augustus, praising him for ending the bad old days of civil war, and ushering in a new golden age of peace and prosperity. For the framers of the Constitution, a “New Age” had dawned with the birth of the United States.