1) Dimly 2) Emptily 3) Expressionlessly 4) Gormlessly 5) In a blank manner 6) In every respect 7) Inanely 8) Indifferently 9) One way to stare 10) Stupidly 11) Totally 12) Vacantly 13) Vacuously 14) Without expression Found on https://www.crosswordclues.com/clue/blankly
Blank'ly adverb 1. In a blank manner; without expression; vacuously; as, to stare blankly . G. Eliot. 2. Directly; flatly; point blank. De Quincey. Found on http://www.encyclo.co.uk/webster/B/62
without expression or understanding: She stared blankly at her inquisitors. · in every respect; totally; fully: He blankly denied ever saying such a thing. Found on https://www.infoplease.com/dictionary/blankly