Failure to perform a task or fulfill an obligation, especially failure to meet a financial obligation: in default on a loan.
Law Failure to make a required court appearance.
The failure of one or more competitors or teams to participate in a contest: won the championship by default.
Computer Science A particular setting or value for a variable that is assigned automatically by an operating system and remains in effect unless canceled or overridden by the operator: changed the default for the font in the word processing program.
A situation or condition that obtains in the absence of active intervention.
v.
de·fault·ed, de·fault·ing, de·faults
v.
intr.
To fail to do what is required.
To fail to pay money when it is due.
To fail to appear in court when summoned.
To lose a case by not appearing.
Law
To fail to appear in court when summoned.
To lose a case by not appearing.
To fail to take part in or complete a scheduled contest.
v.
tr.
To fail to perform or pay.
Law To lose (a case) by failing to appear in court.
To fail to take part in or complete (a contest, for example).
[Middle English defaute, from Old French, from past participle of defaillir, to fail, grow weak : de-, intensive pref.; see de- + faillir; see fail.] de·fault'er n.
[di-fawl-ter] 
tər