unwitnessed

adj

1. Not witnessed.

   “With added sorrow she had her interred there by torch-light—herself sole mourner. It was a relief to be unwitnessed.”

   “Her fate has absorbed Britons, touching the nation’s sense of pity and outrage in a way unwitnessed since the murders of two 10-year-old girls, Holly Wells and Jessica Chapman, in the village of Soham in 2002.”

verb

1. (form-of, participle, past)simple past and past participle of witness