Correct spelling for the English word "Splitpease" is [splˈɪtpiːz], [splˈɪtpiːz], [s_p_l_ˈɪ_t_p_iː_z] (IPA phonetic alphabet).
The word "splitpease" comes from Middle English, specifically from the combination of the words "split" and "pease".
The term "split" refers to the act of splitting, or separating, something into two parts. In this case, it refers to the action of splitting green peas in half. "Pease" is an archaic plural form of the word "pea", referring to a small, round, edible legume.
The combination of "split" and "pease" ultimately gives us the word "splitpease", which is an older term for split peas. Split peas are dried peas that have been split in half, making them easier to cook and commonly used in soups and stews.