Ripper

wiktionary

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rip +‎  -er; originated 1605–15. 

Compare rip(“a basket”), or riparian(“relating to a river bank”).

etymonline

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ripper (n.)

1610s, "one who or that which rips," in any sense of that word, originally chiefly in technical use and slang, agent noun from rip (v.).

The meaning "killer who mutilates his victims" (1890) is from Jack the Ripper, the notorious London serial murderer of 1888-1891, whose nickname contains a pun on ripper in sense of "tool for ripping" old slates, etc. (1823) and the slang meaning "very efficient or excellent person or thing, a 'ripping' fellow" (1838), from ripping (q.v.) in the sense of "excellent, splendid."