indentyoudaoicibaDictYouDict[indent 词源字典]
indent: Etymologically, English has two separate words indent, although they have converged to a considerable extent over the centuries (particularly in the virtually shared derivative indentation). The one meaning ‘(make) a hole or depression’ [14] is simply a derivative of dent, which itself probably originated as a variant of dint. Indent ‘make notches in’ [14], however, owes its origin to Latin dēns ‘tooth’.

This formed the basis of an Anglo-Latin verb indentāre, which denoted the drawing up of a contract between two parties on two identical documents, which were cut along a matching line of notches or ‘teeth’ which could subsequently be rejoined to prove their authenticity. A particular use of such contracts was between master craftsmen and their trainees, who hence became known as indentured apprentices.
=> dent, dint; dentist[indent etymology, indent origin, 英语词源]
indent (v.)youdaoicibaDictYouDict
early 15c., indenten/endenten "to make notches; to give (something) a toothed or jagged appearance," also "to make a legal indenture," from Old French endenter "to notch or dent, give a serrated edge to," from Medieval Latin indentare "to furnish with teeth," from in- "into, in, on, upon" (see in- (2)) + Latin dens (genitive dentis) "tooth" (see tooth). Related: Indented; indenting. The printing sense is first attested 1670s. The noun is first recorded 1590s, from the verb. An earlier noun sense of "a written agreement" (late 15c.) is described in Middle English Dictionary as "scribal abbrev. of endenture."