respective (adj.)youdaoicibaDictYouDict[respective 词源字典]
mid-15c., "regardful, observing or noting with attention," from Medieval Latin respectivus "having regard for," from Latin respect- past participle stem of respicere (see respect (n.)). Meaning "relating or pertaining severally each to each" is from 1640s.[respective etymology, respective origin, 英语词源]