expeditionyoudaoicibaDictYouDict[expedition 词源字典]
expedition: [15] The Latin verb expedīre originally had the rather mundane meaning ‘free one’s feet’ – from a snare, for example It was formed from the prefix ex- ‘out’ and pēs ‘foot’ (source of English pedal, pedestrian, etc and related to English foot). Its literal meaning was soon lost sight of, progressing via ‘extricate, liberate’ to ‘bring out, make ready’ and ‘put in order, arrange, set right’.

The notion of ‘freeing’ something, enabling it to go forward without hindrance, is reflected in the verb’s English descendant expedite [17]. It also survives in the derived noun expedition, as ‘promptness, dispatch’; in the main, however, this has taken a different semantic route, via ‘sending out a military force’ to ‘long organized journey for a particular purpose’.
=> expedite, foot, pedal, pedestrian[expedition etymology, expedition origin, 英语词源]
expedition (n.)youdaoicibaDictYouDict
early 15c., "military campaign; the act of rapidly setting forth," from Old French expedicion "an expediting, implementation; expedition, mission" (13c.) and directly from Latin expeditionem (nominative expeditio) "an enterprise against an enemy, a military campaign," noun of action from past participle stem of expedire "make ready, prepare" (see expedite). Meaning "journey for some purpose" is from 1590s. Sense by 1690s also included the body of persons on such a journey.