eerily
adv.in a way that is very strange or frightening. You use this to describe a feeling that something is not quite right or is very quiet and empty.
adv.in a manner that is strange, unsettling, or unnatural. Often used to describe a silence or a situation that feels out of place.
“The house was eerily quiet when we arrived.”
“The forest was eerily silent, as if the wind had stopped blowing and the animals had disappeared.”
“The abandoned factory stood eerily against the bright morning sun, its rusted gates swinging in the wind like the fingers of a ghost.”
“Historic accounts describe the hours of work, wages paid and duties given to these children but remain eerily silent on the effects these conditions had on children's bodies.”
From eerie + -ly. Compare Old English earglīċe, earhlīċe (“in a cowardly manner, timidly, fearfully”).
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.