Correct spelling for the English word "haffkinize" is [hˈafkɪnˌa͡ɪz], [hˈafkɪnˌaɪz], [h_ˈa_f_k_ɪ_n_ˌaɪ_z] (IPA phonetic alphabet).
To immunize with the Haffkine cholera or plague serum against one or the other disease.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.