fidelity
n.
early 15c., "faithfulness, devotion," from Middle French fidélité (15c.), from Latin fidelitatem (nominative fidelitas) "faithfulness, adherence, trustiness," from fidelis "faithful, true, trusty, sincere," from fides "faith" (see faith). From 1530s as "faithful adherence to truth or reality;" specifically of sound reproduction from 1878.
〔李〕[fid=to trust信任；-elity (-al+-ity) n.=the quality表性质→“the quality of being trusted可被信任之品质”→] n.① faithfulness;loyalty忠诚；忠实