From Longman Dictionary of Contemporary Englishninenine /naɪn/ ●●● S2 W2 number 1 HMNthe number 9 He’s only been in this job for nine months. We open at nine (=nine o'clock). Kay was taught by her mother till she was nine (=nine years old).2 → nine times out of ten3 → a nine days’ wonder4 → have nine lives → dressed up to the nines at dressed(4), → be on cloud nine at cloud1(5)Origin nine Old English nigon