Webster's Revised Unabridged Dictionary · 1913

Naiveté

Naiveté , noun

[F. See Naive, and compare Nativity.]

1.
The state or quality of being naive; lack of sophistication or worldliness.
A story which pleases me by its naiveté -- that is, by its unconscious ingenuousness. — De Quincey
2.
An act displaying naivete; a naive remark or action.

Also: Naivete