Baretti: A dictionary of the English and Italian languages
Segréto, s. m.
1. secret, mystery. Tenere il —,to keep the secret; 2. the bottom of one's heart. Finge d'amarmi, ma nel — suo mi vuol ogni male, he pretends to love me, but in the bottom of his heart he hates me mortally;3. a confidant; 4. secret, receipt, special remedy;5. secret, way, means of doing any thing, knack.
Florio: a worlde of wordes, or most copious, dictionarie in Italian and English