Definition of "inexpressibly"

To my mind there has always been something inexpressibly awful in family feuds.

1864, J[oseph] Sheridan Le Fanu, “In which Lake under the Trees of Brandon, and I in My Chamber, Smoke Our Nocturnal Cigars”, in Wylder’s Hand. […], New York, N.Y.: Carleton, […], published 1865, page 63

Inexpressibly tired of this anxious intricate search I threw myself down on the soft moss to rest for a while, but the fatigue conquered the fears of the lonely forest, and I cannot now tell how long I dozed.

1886, Peter Christen Asbjørnsen, translated by H.L. Brækstad, Folk and Fairy Tales, page 281