白白 is read as はくはく (hakuhaku) and means clear.
はくはく
hakuhaku
しろ
blank space
はくじん
unlicensed prostitute
はくしょ
white paper (government report)
しろい
white
しろばい
motorcycle police
しらこ
albino
しらむ
to grow light
はくじつ
bright sunshine
しろみず
color of water after washing rice (colour)
しらき
plain wood
はくい
commoner without rank (in ancient China)
しらが
white hair