Correct spelling for the English word "Midlenting" is [mˈɪdləntɪŋ], [mˈɪdləntɪŋ], [m_ˈɪ_d_l_ə_n_t_ɪ_ŋ] (IPA phonetic alphabet).
There is no known word "Midlenting" in the English language, and therefore, no etymology can be provided for it. It is possible that the word has been misspelled or is derived from a different language or domain.