They were either irretrievably lost to us, or never available at all.
Either he would understand or what they had slowly built between them was irretrievably lost.
"But so much knowledge was irretrievably lost, especially in my Craft."
And in the holocaust that followed, so much was irretrievably lost.
It could become the symbol of an irretrievably lost opportunity.
After all, she did not yet know that her own deed was irretrievably lost.
Had I done so, he would have been irretrievably lost!
In moments, the sunlight was gone as if it had been irretrievably lost.
Instead, she seemed to be taking after her father, who had become irretrievably lost in drug and alcohol addiction.
Without their guidance, I would be permanently and irretrievably lost.