Latin abbreviation: Votis Tricennalibus Multis Quadragennalibus - vows (prayers) on the 30th anniversary [of the emperors rule], more for his [hoped for] 40th anniversary.
The tricennalia were celebrations of the third decennalia, three decades
of rule. No coin is known bearing the word tricennalia. Naturally, very
few Emperors reigned long enough to enjoy such a festival. VOTIS XXX is
found on the coins of Maximian and Constantine I; VOT XXX AVGG on coins
of Maximian; VOTIS XXX MVLTIS XXXX on those of Constantine II and
Julian II; and VOT XXX MVLT XXXX on those of Julian II, Honorius
Valentinian III and Eudoxia.