daylight saving time
noun(abbreviation DST)
(also daylight time)
(both North American English) (British English summer time)
[uncountable]the period during which in some countries the clocks are put forward one hour, so that it is light for an extra hour in the evening 夏令时（有些国家实行夏时制，将时钟拨快一小时，以节约照明能源）