ex·ter·nal-com·bus·tion engine英ɪkˈstɜːnəlkəmˈbʌstʃən美ɪkˈstɝnəlkəmˈbʌstʃənAHDĭk-stûrʹnəl-kəm-bŭsʹchən 基本英英 ph.外燃机如蒸汽机等 Noun: a heat engine in which ignition occurs outside the chamber cylinder or turbine in which heat is converted to mechanical energy