(idiomatic, singular only) (United States English, pejorative) The dollar, satirically characterized as a being a god.
Wiktionary
Origin of Almighty-dollar
Most sources hold this to be a coinage of Washington Irving, alluding to "AlmightyGod", although a Philadelphia newspaper also used the phrase at approximately the same time and Ben Jonson had used "almighty gold" in 1616 in Epistle to Elizabeth, Countess of Rutland.