Though this question has already been answered, I wanted to add one more thing. As Juan and Miguel already pointed out, ""aún" (with written stress) should be translated as "still" or "yet" (in thi case it is a synonym of "todavía"). For example: Aún tengo tiempo. I still have time. ¿No has escuchado nada aún? Have you not heard anything yet? Now, "aun" (with no written stress) means "even", but this use is rare today in Spanish. Le daré una casa y aun un auto si es que me lo pide. I will give him a house and even a car if he asks for it. No me quiso decir la respuesta, ni aun cuando su padre se lo pidió. He did not want to tell me the answer, not even when his father asked him to. As for the word "hasta", it can be translated as "even", just as the word "incluso" can be translated as "even". They are completely interchangeable and there is absolutely no difference. Ella hasta habla latín. Ella incluso habla latín She even speaks Latin. Nosotros hasta le dimos los libros. Nosotros incluso le dimos los libros. We even gave him the books. Now, you have to take into acount that the negative "even" in Spanish is somewhat different. "Not even" has to be translated as "ni siquiera". There is only one negative form. Ella ni siquiera hablar latín She does not even speak Latin. Nosotros ni siquiera le dimos los libros. We did not even give him the books. I hope this helps you.

En la mayoría de los casos, "aún" comparte significado con "todavía". Con menor frecuencia comparte significado con "incluso". Me atrevería a decir que lo segundo sucede cuando precede a un gerundio.

La traducción de la segunda frase sería más bien: I'm still hungry. De todos modos, en casos POCO frecuentes, "aun" puede significar, como tú dices, even: Aún estudiando mucho, no he aprobado: Even if (although) I studied hard, I didn't succeed.