systematic (adj.)youdaoicibaDictYouDict[systematic 词源字典]
1670s, "pertaining to a system," from French systématique or directly from Late Latin systematicus, from Greek systematikos "combined in a whole," from systema (genitive systematos); see system. From 1789 as "methodical," often in a bad sense, "ruthlessly methodical." Related: Systematical (1660s); systematically.[systematic etymology, systematic origin, 英语词源]