default
verb [ I ] uk/dɪˈfɒlt/ us/dɪˈfɑːlt/
拖欠，不履行债务；违约
to fail to do something, such as pay a debt, that you legally have to do
People who default on their mortgage repayments may have their home repossessed. 未能按期偿还抵押贷款者，其房屋可能会被收回。
Phrasal verb
default to something （计算机）默认…，缺省为…，预设为…
If a computer defaults to a way of operating, it automatically uses it if you do not intentionally change it.
default
noun uk/dɪˈfɒlt/ /ˈdiː.fɒlt/ us/dɪˈfɑːlt/
(RESULT)
[ U ]默认结果，既定结果；预置值；缺省值
the thing that exists or happens if you do not change it intentionally by performing an action
Unless something else is agreed, the default is to meet at the hotel at 7.00 p.m. 如果没有变化，按约定下午7点在酒店见面。
The computer will take 0 as the default value, unless you type in something different. 如果不键入其他数值，计算机就把0当作默认值。
formal In default of (= because there is not) any better alternative, we will have to proceed with the original plan. 由于没有更好的方案，我们将只好按原定计划行事。
(FAIL)
[ C or U ]拖欠，不履行债务;违约
a failure to do something, such as pay a debt, that you legally have to do
Defaults on loan repayments have reached 52,000 a month. 拖欠贷款的现象每月已达52000宗。
Any default on your mortgage payments may mean you will lose your house. 不按时偿还抵押贷款就意味着可能会失去房子。
Since they refuse to reply, I think we've won the argument by default (= because of their failure to act). 由于他们拒绝答复，我认为我们自动赢得了这场辩论。
The national student loan default rate (= the number of people failing to pay) is estimated at one in ten. 据估计，约有十分之一的人拖欠偿还国家助学贷款。