portentously

adv

1. In an ominous manner.

   “The cold light of the moon touched every face with unnatural paleness; and the silence was unbroken and portentously profound.”

   “At that moment a long, scraggy individual in a checked suit poked his head into the bar, looked around portentously, whistled mysteriously to my informant, and jerked his thumb and head in the direction of the door.”

   “Shirky ends the story of the lost Sidekick by asking, portentously, “What happens next?”—no doubt imagining future waves of digital protesters.”

2. In a pompous manner.