taru-adjective, adverb taking the 'to' particle
dreary; dismal; lonely; mournful
Literary and somewhat archaic adjective describing a desolate, lonely, or melancholy atmosphere, often of wind, rain, or a scene. Used with 〜たる or 〜と.
蕭々たる秋雨が降り続く。
A dreary autumn rain continues to fall.
蕭々とした風の音が聞こえる。
I can hear the mournful sound of the wind.
A more common modern adjective for a lonely, desolate feeling, whereas 蕭々 is literary and archaic.
A similar literary word meaning desolate or bleak, often used for scenes or landscapes.
The exact derivation is uncertain. The kanji 蕭 originally refers to a type of plant (wormwood) and by extension came to suggest desolation or a mournful rustling sound. The reduplicated form 蕭々 is a classical Chinese-derived literary expression.