Here is a word which derives from the verb negare, to deny. But this is the adjective form, and has a special meaning to describe someone who is the opposite of gifted in some area. In English we might say "no good at" for the same concept. People will often describe their own deficiencies in these terms.
Sono negato per la matematica.
I'm bad at math.
Sono negata per la cucina, ho fatto anche un corso, ma niente.
I have no aptitude for cooking; I even took a course, but it was no use.
