Denshi Jisho — Online Japanese dictionary

目覚まし めざまし 1: (Abbreviation) alarm clock;
2: opening one's eyes; keeping one's eyes open;
3: type of candy given to a child after it wakes up from a nap
Common word, Noun 
目覚ましい めざましい brilliant; splendid; striking; remarkable
Common word, Adjective 
目覚まし時計 めざましどけい alarm clock
Common word, Noun 
目覚まし時計 めざましとけい alarm clock
Noun 

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