record-breaking

ˈrecord-ˌbreaking adjective [only before noun]
a record-breaking number, level, performance, or person is the highest, lowest, biggest, best etc of its type that has ever happened or existed:
• his record-breaking flight across the Atlantic
—record-breaker noun [countable]

Oxford Advanced Learner's Dictionary

record-breaking

ˈrecord-breaking ; adjectiveonly before noun

• a record-breaking jump

Main entry: record-breakerderived

Cambridge Advanced Learner's Dictionary

record-breaking

record-breaking /ˈrek.ɔːdˌbreɪ.kɪŋ/ US /-ɔːrd-/
adjective [before noun]
better, bigger, longer, etc. than anything else before:
Company profits are rising and it looks as though this is going to be a record-breaking year.

Collins COBUILD Advanced Learner’s English Dictionary

record-breaking

ADJ: ADJ n
A record-breaking success, result, or performance is one that beats the previous best success, result, or performance.
Australia's rugby union side enjoyed a record-breaking win over France.

record-breaking

adjective