a leather seat for a rider on a horse 马鞍 a seat on a bicycle or motorcycle （自行车或摩托车的）车座 
a piece of meat from the back of an animal （动物的）脊肉 a saddle of lamb 一小羊
Word OriginOld English sadol, sadul, of Germanic origin; related to Dutch zadel and German Sattel, perhaps from an Indo-European root shared by Latin sella ‘seat’ and sit.
Idioms
in the saddle
in a position of responsibility, control or authority 担任领导职务；掌权；在位 It's actually good to be back in the saddle after the holidays. 假期过后回到马鞍上真的很不错。 He wanted a united party, with himself firmly in the saddle. 他想要一个团结的党，把自己牢牢地牢牢地牢牢扎在马鞍上。
riding a horse 骑马