Pronunciation: [ˈɪnsənʃən] (IPA)
Correct spelling for the English word "Incension" is [ˈɪnsənʃən], [ˈɪnsənʃən], [ˈɪ_n_s_ə_n_ʃ_ə_n] (IPA phonetic alphabet).
Correct spelling for Incension