An exclamation of anger or frustration. Fuck! I can't believe I missed the bus again.
An expression of surprise or shock. Fuck! Did you see that car almost hit the pedestrian?
Used to express disbelief or amazement. Fuck, I can't believe you actually won the lottery!
Fuck! I just stubbed my toe on the table.
Used to express annoyance or irritation. Oh, fuck, I forgot my keys at home.