The term "split-half" is a modern English compound noun formed from two native Germanic words. "Split" originates from Middle Dutch and Low German roots meaning to cleave or divide, while "half" descends from the Old English word for one of two parts, a concept deeply rooted in Proto-Germanic. Combined in the 20th century within the field of psychometrics, the compound literally describes the core methodological action: splitting a whole test into two halves. The logic is transparent, moving from the concrete physical act of division to an abstract statistical procedure for measuring consistency, where the "half" refers to each resulting parallel section of the assessment tool.

Structure: split (divided) + half (one of two equal parts) split: From Middle Dutch splitten, of Germanic origin. In this compound, it functions as a modifier meaning "divided." half: From Old English healf, of Germanic origin. In this compound, it functions as a noun meaning "one of two equal parts."