Correct spelling for the English word "Expolish" is [ɛkspˈɒlɪʃ], [ɛkspˈɒlɪʃ], [ɛ_k_s_p_ˈɒ_l_ɪ_ʃ] (IPA phonetic alphabet).
There is no recognized word expolish in the English language. It seems to be a non-standard or misspelled term. If you meant to ask about the word polish, its etymology can be traced back to the Middle English word polischen, which came from Old French poliss- (stem of polir) meaning smoothen, polish. This in turn originated from Latin polire meaning to polish or to make smooth.