a splitting headache — a very bad headache
collocationB1IELTS 5+informalcommon
A very painful, intense headache — the kind that makes it hard to think or focus.
Pattern: [subject] + have (got) + a splitting headache
In use
- I've got a splitting headache — I can barely look at the screen.describing a symptom
- A: Do you fancy coming out tonight?
B: I'd love to, but I've got a splitting headache.declining plans
Common mistake
✗ I have a splitting head.
✓ I've got a splitting headache.
'Splitting' goes with 'headache', not 'head' — it's a fixed pairing.
Don't confuse it
'A splitting headache' is severe; 'a slight headache' is mild.