vacantly

From vacant +‎ -ly.

vacantly (comparative more vacantly, superlative most vacantly)

1. In a vacant manner; inanely or foolishly.
   • 1988, Anthony Grey, Peking: A Novel of China's Revolution, 1921-1978‎^[1], Little, Brown and Company, →ISBN, →LCCN, →OCLC, page 580:

     Mao gave no indication that he had heard or understood Jakob; his clouded eyes were fixed vacantly on one of the long windows of the old Ming dwelling beyond which the waters of Chung Nan Hai — the Central and South lakes — sparkled in the afternoon sunshine.