taru-adjective, adverb taking the 'to' particle
lush; overgrown; exuberant (of vegetation)
Archaic literary word describing thick, flourishing plant growth. Used as a taru-adjective or adverb with と. Not used in modern everyday Japanese.
In old Chinese-style poetry, mountains are described as being lush and overgrown with 蓊鬱として.
Archaic kanji spelling; both characters are uncommon and the word itself is rare.
Variant kanji spelling; equally rare and archaic.
The exact derivation is uncertain; the kanji 蓊 and 鬱 both relate to thick growth, and the word is a classical Chinese borrowing.