Entry 1 sense Webster, 1913 Streptococcus /strĕpˌ-tək-ôk'-əs/ · Strep·to·coc·cus · IPA /ˌstɹɛptəˈkɑkəs/ 01 n. A long or short chain of micrococci, more or less curved. pl. Streptococci ((#)) 1. A long or short chain of micrococci, more or less curved.(Biol.)