neutral – нейтральный; средний, неопределенный; безразличный

neutral (adj.) (сочетание разнородных элементов, которые в некой пропорции нейтрализуют друг друга); из среднефранцузского «neutralis» - средний род; из «neuter»
late 15c., "composed of contrasting elements which, in proper proportion, neutralize each other," from Middle French neutral, from Latin neutralis "of neuter gender," from neuter (see neuter (adj.)). Chemistry sense is from 1660s. Sense of "not taking sides in a fight" (1540s) probably is from a similar meaning in Medieval Latin.

neuter (adj.) (средний род, не мужской и не женский); из латинского «neuter» - средний род, дословно – ни один, не другой; из «ne-» - нет + «uter» - любой из двух
late 14c., of grammatical gender, "neither masculine nor feminine," from Latin neuter "of the neuter gender," literally "neither one nor the other," from ne- "not, no" (see un-) + uter "either (of two)" (see whether). Probably a loan-translation of Greek oudeteros "neither, neuter." In 16c., it had the sense of "taking neither side, neutral."

См. «neither» - некоторый, из которых (из коих)