ruseyoudaoicibaDictYouDict[ruse 词源字典]
ruse: [15] Ruse and rush ‘hurry’ are ultimately the same word. Both come from Old French ruser ‘drive back, detour’. From this was derived the noun ruse, which brought the sense ‘detour, deviation’ with it into English. It was used in the context of a hunted animal dodging about and doubling back on its tracks to throw off its pursuers, and this led in the early 17th century to the emergence of the metaphorical sense ‘trick, stratagem’.

The precise origins of Old French ruser are uncertain. It is generally referred to Latin recūsāre ‘refuse’, source of English recusant and possibly of refuse, but it has also been speculated that it came via a Vulgar Latin *rursāre or *rusāre from Latin rursus ‘backwards’.
=> rush[ruse etymology, ruse origin, 英语词源]
ruse (n.)youdaoicibaDictYouDict
early 15c., "dodging movements of a hunted animal;" 1620s, "a trick," from Old French ruse, reuse "diversion, switch in flight; trick, jest" (14c.), back-formed noun from reuser "to dodge, repel, retreat; deceive, cheat," from Latin recusare "deny, reject, oppose," from re-, intensive prefix (see re-), + causari "plead as a reason, object, allege," from causa "reason, cause" (see cause (n.)). It also has been proposed that the French word may be from Latin rursus "backwards," or a Vulgar Latin form of refusare. Johnson calls it, "A French word neither elegant nor necessary." The verb ruse was used in Middle English.