Definition of smithian:
(adj) :
(economics) Of or characteristic of the theories of the political economist Adam Smith (1723–1790).
(adj) :
Of, pertaining to, or characteristic of a person bearing the surname Smith.
(adj) :
(geology) Of a regional geological stage of the Early Triassic epoch (249.7 – 247.4 Ma; preceded by the Dienerian and followed by the Spathian).