Zmizni!

Pronounced: zmee-znee

The imperative of 'zmiznúť', it literally means 'disappear!' But figuratively, and practically it means 'be off', 'go away', 'be gone'. It's the sort of thing you would say to a child who's annoying you. Imagine the America Grandpa saying, "Go cut me a switch."

Example:
"Zmizni!" - "Go away!"
"Mám ťa dosť. Zmizni!" - "I've had enough of you. Be gone!"

Related words:
zmiznúť - to disappear
vymiznúť - to vanish (i.e. the dinosaurs 'vymizli')
podieť sa - to go away (somewhere)

Pravda

Pronounced: Prav-dah

A noun, it means 'fact'. But I would translate it closer to 'veracity', because something 'has veracity' in English, which is what they say in Slovak.

Example:
"Máte pravdu." - "You're right."

Related words:
správne - adj. right
opraviť/opravovať - perfective and imperfective of 'to be correct'

Chyba

Pronounced: Ch-ee-ba

A noun, it means 'error'. The nominative and accusative plural is 'chyby'.

Example:
"Je úplne bez chyby." - "It's absolutely correct (lit. It's totally without errors)."

Related words:
chybný - adj. erronous
omyl - mistake