Denshi Jisho — Online Japanese dictionary

欠ける かける 1: to be chipped; to be damaged; to be broken;
2: to be lacking; to be missing;
3: to be insufficient; to be short; to be deficient; to be negligent toward;
4: (of the moon) to wane; to go into eclipse
Common word, Ichidan verb, Intransitive verb 

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