Falta (en. Lack)
/ˈfal.ta/
Slang Meanings
Lack of knowledge on a topic.
Don't worry, it's normal to have a deficiency in math at first.
No te preocupes, es normal que tengas falta en matemáticas al principio.
Lack of respect in informal contexts.
That attitude was a brutal mistake, that's not how it's done.
Esa actitud fue una falta brutal, no se hace así.