ˈkɒz.mɒs kɹiːˈeɪʃən ɛɡ.ˈzɪs.təns ˈmæk.ɹəʊˌkɒ.zəm ˈmæk.ɹəˌkɑ.zəm ˈjuːnɪˌvɜːs ˈjuːnəˌvɝs wɜːld wɝld wɵːld everything that exists anywhere they study the evolution of the universe the biggest tree in existence any of various mostly Mexican herbs of the genus Cosmos having radiate heads of variously colored flowers and pinnate leaves; popular fall-blooming annuals