1
- a brief or temporary failure of concentration, memory, or judgement（注意力, 记忆）短暂丧失; （判断）失误, 差错：
a lapse of concentration in the second set cost her the match.
第二局时她因一时走神而输掉了比赛。
1.1
- a weak or careless decline from previously high standards（因意志不坚定或不慎而）堕落：
tracing his lapse into petty crime.
追踪他小打小闹地作奸犯科的缘由。
1.2
- Law the termination of a right or privilege through disuse or failure to follow appropriate procedures【律】（权利, 特权的）终止; 丧失。
2
- an interval or passage of time时间间隔, 时间段：
there was a considerable lapse of time between the two events.
两次事件之间有一段相当长的间隔。
no obj.
1
- (of a right, privilege, or agreement) become invalid because it is not used, claimed, or renewed; expire（权利, 特权的）终止; 丧失; （协议的）到期, 满期; 失效：
he let his membership of CND lapse.
他中止了自己的核裁军运动成员的身份。
1.1
- (of a state or activity) fail to be maintained; come to an end（状态, 活动）中止, 结束：
if your diet has lapsed it's time you revived it.
如果你已停止节食, 现在就应该恢复。
1.2
- (of an adherent of a particular religion or doctrine) cease to follow the rules and practices of that religion or doctrine（宗教或学说的追随者）背离, 放弃：
as adj. lapsed a lapsed Catholic.一个离经叛道的天主教徒。
2
lapse into
pass gradually into (an inferior state or condition)逐渐往坏里变化; 堕落为, 陷入：the country has lapsed into chaos.
该国已陷入混乱状态。
2.1
- revert to (a previous or more familiar style of speaking or behaviour)回复（先前或习惯的言语或行为方式）：
the girls lapsed into French.
姑娘们又改说她们习惯的法语了。
词源
late Middle English: from Latin lapsus, from labi 'to glide， slip， or fall'; the verb reinforced by Latin lapsare 'to slip or stumble'.