thief (n.)

古英语 þeof “小偷，强盗”，源自原始日耳曼语 *theuba-（也源自古弗里西亚语 thiaf，古撒克逊语 thiof，中古荷兰语和荷兰语 dief，古高地德语 diob，德语 dieb，古诺尔斯语 þiofr，哥特语 þiufs），一个起源不明的词。

A thief takes other people's property without their knowledge ; a robber takes it openly, whether or not resistance is offered : in a looser sense, thief is often applied to one who takes a small amount, and robber to one who takes a large amount. [Century Dictionary, 1895]

thief “小偷”在未经他人同意的情况下拿走别人的财产； robber “强盗”则公然拿走，无论是否有抵抗：在较宽松的意义上， thief 通常用于指拿走少量财物的人，而 robber 则用于指拿走大量财物的人。[世纪词典，1895年]