ガイ 
() harm () injury
                          
がい (n) injury, harm, evil influence, damage
がいする (vs-s,vt) (1) to injure, to damage, to harm, to hurt, (2) to kill, (3) to hinder, to obstruct
がいちゅう (n,adj-no) harmful insect, noxious insect

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Etymologies: 中文字譜 : 説文解字