ぴかぴか光る[pikapikahikaru] to sparkle
旭光[kyokkou] rays of the rising sun
威光[ikou] power
稲光[inabikari] (flash of) lightning
曳光弾[eikoudan] tracer bullet

栄光[eikou] glory
円光[enkou] halo
炎光[enkou] flame
黄道光[koudoukou] zodiacal light
可視光線[kashikousen] visible ray

データの先頭[deetanosentou] beginning of data
一頭[ittou] one large animal (horses, cattle, etc.)
一頭立て[ittoudate] one-horse (carriage)
咽頭[intou] pharynx
駅頭[ekitou] station

音頭[ondo] leading a group of people
会頭[kaitou] society president
街頭[gaitou] in the street
核弾頭[kakudantou] nuclear warhead
巻頭[kantou] opening page of book