Pronunciation: [d͡ʒˈɛntə͡lsˌɛks] (IPA)
Correct spelling for the English word "gentlesex" is [d͡ʒˈɛntə͡lsˌɛks], [dʒˈɛntəlsˌɛks], [dʒ_ˈɛ_n_t_əl_s_ˌɛ_k_s] (IPA phonetic alphabet).
Correct spelling for gentlesex