Synonyms:
ingenuous, artless
Meaning: characterized by an inability to mask your feelings; not devious; "an ingenuous admission of responsibility"
Synonyms:
innocent, ingenuous
Meaning: lacking in sophistication or worldliness; "a child's innocent stare"; "his ingenuous explanation that he would not have burned the church if he had not thought the bishop was in it"
Usage examples
Then they gave an audible gasp, induced by an ingenuous compound of amazement, disappointment, and admiration.
The ingenuous police of the Restoration beheld the populace of Paris in too "rose-colored" a light; it is not so much of "an amiable rabble" as it is thought.