portentously

portentous +‎ -ly

• IPA^(key): /pɔː(ɹ)ˈtɛn.təs.li/

portentously (comparative more portentously, superlative most portentously)

1. In an ominous manner.

   Synonym: ominously

   • 1834, L[etitia] E[lizabeth] L[andon], chapter XXXVIII, in Francesca Carrara. […], volume III, London: Richard Bentley, […], (successor to Henry Colburn), →OCLC, page 318:

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

   • 1946, George Johnston, Skyscrapers in the Mist, page 121:

     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.

   • 2010 September 27, Malcolm Gladwell, “Small Change”, in The New Yorker‎:

     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.