feeyoudaoicibaDictYouDict[fee 词源字典]
fee: [14] Fee is a word bequeathed to modern English by the feudal system (and indeed it is closely related etymologically to feudal). It came via Anglo-Norman fee from medieval Latin feodum or feudum (source also of feudal [17]). This denoted ‘land or other property whose use was granted as a reward for service’, a meaning which persists in its essentials in modern English ‘payment for work done’.

The secondary signification of fee, ‘feudal estate’, is no longer a live sense, but it is represented in the related fief [17], a descendant of feodum, which English acquired through French rather than Anglo-Norman. The ultimate derivation of the medieval Latin term itself is not altogether clear, although it is usually assigned to an unrecorded Frankish *fehuōd, literally ‘cattle-property’ (*fehu has related forms in Old English féoh ‘cattle, property’ and Old Norse fé ‘cattle, money’ – joint sources of the first syllable of English fellow – and in modern German viehe ‘cattle’; they all go back ultimately to Indo- European *peku-, ancestor of a wide range of words meaning ‘cattle’ which, since in former times cattle were symbolic of wealth, in many cases came to signify ‘property’ too).
=> fellow, feudal, fief[fee etymology, fee origin, 英语词源]
fee (n.)youdaoicibaDictYouDict
Middle English, representing the merger or mutual influence of two words, one from Old English, one from an Old French form of the same Germanic word, and both ultimately from a PIE root meaning "cattle."

The Old English word is feoh "livestock, cattle; movable property; possessions in livestock, goods, or money; riches, treasure, wealth; money as a medium of exchange or payment," from Proto-Germanic *fehu- (cognates: Old Saxon fehu, Old High German fihu, German Vieh "cattle," Gothic faihu "money, fortune"). This is from PIE *peku- "cattle" (cognates: Sanskrit pasu, Lithuanian pekus "cattle;" Latin pecu "cattle," pecunia "money, property").

The other word is Anglo-French fee, from Old French fieu, a variant of fief "possession, holding, domain; feudal duties, payment" (see fief), which apparently is a Germanic compound in which the first element is cognate with Old English feoh.

Via Anglo-French come the legal senses "estate in land or tenements held on condition of feudal homage; land, property, possession" (c. 1300). Hence fee-simple (late 14c.) "absolute ownership," as opposed to fee-tail (early 15c.) "entailed ownership," inheritance limited to some particular class of heirs (second element from Old French taillir "to cut, to limit").

The feudal sense was extended from landholdings to inheritable offices of service to a feudal lord (late 14c.; in Anglo-French late 13c.), for example forester of fe "a forester by heritable right." As these often were offices of profit, the word came to be used for "remuneration for service in office" (late 14c.), hence, "payment for (any kind of) work or services" (late 14c.). From late 14c. as "a sum paid for a privilege" (originally admission to a guild); early 15c. as "money payment or charge exacted for a license, etc."