Ingenious and ingenuous arose from the same Latin root meaning “to beget, give birth” and once had the same meaning. They are now distinct from each other and are not synonyms. Ingenious means “characterized by cleverness” or “cleverly inventive,” as in contriving new explanations or methods: an ingenious device; ingenious designers. Both ingenious and ingenuous originally meant “of honorable or free birth, noble in character; open, frank, candid,” senses that exist in Latin. Since the second half of the 17th century, ingenuous has acquired the additional sense “naively open, innocently frank”: an ingenuous and sincere statement; a thug with the ingenuous eyes of a choirboy.

Did you mean anxiousness?