Wiktionary
unpresidential
a. In a manner inappropriate for a president.
WordNet
unpresidential
adj. not presidential; "very unpresidential behavior" [ant: presidential]
Usage examples of "unpresidential".
Almost all of their attention was on the TV screen, which cut away from the most unpresidential images of the new president to new scenes of the ruin that had without warning overtaken Indianapolis.