taru-adjective, adverb taking the 'to' particle
past events fading into distant memory
Archaic literary expression describing how memories of the past become hazy and remote. Used as a taru-adjective or adverbially with と.
See also: 往事茫々
往事渺茫として思い出せない。
The past events are so distant that I cannot recall them.
往事渺茫たる思いにふける。
I am lost in thoughts of the far-off past.
Variant spelling with the same meaning and archaic register; 渺茫 and 茫々 are interchangeable here.
A yojijukugo of Chinese origin, combining 往事 (past events) and 渺茫 (vast and indistinct). The exact historical derivation is uncertain.