Meaning

verb stay the same; remain in a certain state

verb continue in a place, position, or situation

verb be left; of persons, questions, problems, results, evidence, etc.

originFrom Middle English remainen, from Old French remain-, stressed stem of remanoir, from Latin remaneō, maneō, from Proto-Indo-European *men- (“to stay”). Displaced native Middle English beliven, bliven (“to remain”) (from Old English belīfan (“to remain, stay”)) due to confluence with related Middle English beleven (“to leave behind”), with which it merged. More at beleave and belive.

Etymology from Wiktionary, CC BY-SA 3.0