for certain

Từ điển WordNet v3.1 - WordNet Dictionary

adverb

definitely or positively ('sure' is sometimes used informally for 'surely')
- the results are surely encouraging
- she certainly is a hard worker
- it's going to be a good day for sure
- they are coming, for certain
- they thought he had been killed sure enough
- he'll win sure as shooting
- they sure smell good
- sure he'll come
• Syn:
surely, certainly, sure, for sure, sure enough, sure as shooting
• Derived from adjective:
certain (for: certainly), sure (for: surely)
• Usage Domain:
colloquialism