alarm clock

Từ điển tiếng Anh - Cambridge Advanced Learners Dictionary

aˈlarm ˌclock noun countable ( also alarm ) [ alarm clocks ] UK US
<A > a clock that you can set to wake you up at a particular time with a loud noise
• My alarm clock went off at 7.30.
• I've set the alarm for 7.30.
Thesaurus⁺: ↑Watches and clocks
 
• Didn't you hear your alarm clock going off this morning?
• He woke up with a jerk when the alarm clock went off.
• This alarm clock takes two medium-sized batteries.
• Anne's alarm clock rang for half an hour before she woke.
• He set his alarm clock for 7.00 a.m.