taru-adjective, adverb taking the 'to' particle
as if; just like; the very image of
Archaic literary expression used in classical or highly formal writing. Describes something that appears exactly like something else, often with a sense of vivid resemblance. Modern equivalents include まるで～のようだ or さながら.
その光景は宛然として一幅の絵のようであった。
The scene was just like a painting.
彼の話しぶりは宛然、師匠を思わせるものがあった。
His way of speaking was exactly like his master's.