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Old English belifan "remain," intransitive form of belæfan "cause to remain" (see beleave). A general Germanic word (cf. Gothic beleiban, Old High German biliban, German bleiben, Dutch blijven); confused in early Middle English with beleave and merged into it, which gave beleave two clashing senses ("to leave," also "to remain") which might be why the compound word, the cognate of important verbs in other Germanic languages, was abandoned in English and only leave (v.) remains.