The Collaborative International Dictionary of English v.0.48:

Default \De*fault"\, v. i. [imp. & p. p. Defaulted; p. pr. &
   vb. n. Defaulting.]
   1. To fail in duty; to offend.
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            That he gainst courtesy so foully did default.
                                                  --Spenser.
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   2. To fail in fulfilling a contract, agreement, or duty.
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   3. To fail to appear in court; to let a case go by default.
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The Collaborative International Dictionary of English v.0.48:

Default \De*fault"\, n. [OE. defaute, OF. defaute, defalte,
   fem., F. d['e]faut, masc., LL. defalta, fr. a verb meaning,
   to be deficient, to want, fail, fr. L. de- + fallere to
   deceive. See Fault.]
   1. A failing or failure; omission of that which ought to be
      done; neglect to do what duty or law requires; as, this
      evil has happened through the governor's default.
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   2. Fault; offense; ill deed; wrong act; failure in virtue or
      wisdom.
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            And pardon craved for his so rash default.
                                                  --Spenser.
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            Regardless of our merit or default.   --Pope.
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   3. (Law) A neglect of, or failure to take, some step
      necessary to secure the benefit of law, as a failure to
      appear in court at a day assigned, especially of the
      defendant in a suit when called to make answer; also of
      jurors, witnesses, etc.
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   In default of, in case of failure or lack of.
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            Cooks could make artificial birds and fishes in
            default of the real ones.             --Arbuthnot.

   To suffer a default (Law), to permit an action to be called
      without appearing to answer.
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The Collaborative International Dictionary of English v.0.48:

Default \De*fault"\, v. t.
   1. To fail to perform or pay; to be guilty of neglect of; to
      omit; as, to default a dividend.
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            What they have defaulted towards him as no king.
                                                  --Milton.
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   2. (Law) To call a defendant or other party whose duty it is
      to be present in court, and make entry of his default, if
      he fails to appear; to enter a default against.
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   3. To leave out of account; to omit. [Obs.]
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            Defaulting unnecessary and partial discourses.
                                                  --Hales.
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WordNet (r) 3.0 (2006):

default
    n 1: loss due to not showing up; "he lost the game by default"
    2: act of failing to meet a financial obligation [syn:
       default, nonpayment, nonremittal]
    3: loss resulting from failure of a debt to be paid [syn:
       nonpayment, default, nonremittal] [ant: payment]
    4: an option that is selected automatically unless an
       alternative is specified [syn: default option, default]
    v 1: fail to pay up [syn: default, default on] [ant: ante
         up, pay, pay up]

The Free On-line Dictionary of Computing (19 January 2023):

default

    A value or thing to use when none is specified by the
   user.  Defaults are important for making systems behave in a
   predictable way without the user having to give lots of
   "obvious" details.

   For example: the default TCP/IP port for the HTTP
   protocol is 80, the Unix ls command does not list files
   whose names begin with ".", the default number base in most
   contexts is 10 (decimal), the default filename extension for
   Microsoft Word documents is ".doc".

   (2009-02-20)