refuseyoudaoicibaDictYouDict[refuse 词源字典]
refuse: [14] Refuse comes via Old French refuser from an unrecorded Vulgar Latin *refūsāre. It is not altogether clear where this came from, for it has no direct Latin antecedent. One theory is that it represents a blend of Latin recūsāre ‘refuse’ (source of English recusant [16]), a compound verb based on causa ‘cause’, and refūtāre ‘rebut’ (source of English refute [16]), a compound verb based on the element *fūt-, found also in English confute [16].

But another long-established school of thought derives it from refūsus, the past participle of Latin refundere ‘pour back’ (source of English refund [14]) – the underlying notion being of something ‘poured back’ or ‘rejected’. The noun refuse ‘rubbish’ [15] probably comes from Old French refus ‘refusal’, a derivative of refuser ‘refuse’.
[refuse etymology, refuse origin, 英语词源]
refuse (v.)youdaoicibaDictYouDict
c. 1300, from Old French refuser "reject, disregard, avoid" (12c.), from Vulgar Latin *refusare, frequentative form from past participle stem of Latin refundere "pour back, give back" (see refund (v.)). Related: Refused; refusing.
refuse (n.)youdaoicibaDictYouDict
mid-14c., "an outcast;" mid-14c., "a rejected thing, waste material, trash," from Old French refus "waste product, rubbish; refusal, denial, rejection," a back-formation from the past participle of refuser (see refuse (v.)). As an adjective from late 14c., "despised, rejected;" early 15c., "of low quality."