"The lion" is an English equivalent of the Italian phrase il leone. The masculine singular definite article and noun references the male whereas la leonessa refers to the female, "the lioness." The respective pronunciations will be "eel ley-O-ney" and "la LEY-o-NES-sa" in Italian.
Il in Italian means "the" in English.
Il messaggio in Italian is "the message" in English.
Il piede in Italian means "the foot" in English.
Il placet in Italian means "the permit" in English.
Il Cenacolo in Italian is "The Last Supper" in English.
Il pescecane in Italian means "the dogfish" in English.
Il genio in Italian is "the genius" in English.
Il fortunato in Italian means "the lucky one" in English.
"The best!" in English is Il migliore! in Italian.
"The devil" in English is il diavolo in Italian.
"The white" in English is il bianco in Italian.
"The cheese" in English is il formaggio in Italian.