黑素

melanin / black pigment

abbr. for Heilongjiang province 黑龍江|黑龙江[Hei1 long2 jiang1]

black / dark / sinister / secret / shady / illegal / to hide (sth) away / to vilify / (loanword) to hack (computing)

raw silk / white / plain, unadorned / vegetarian (food) / essence / nature / element / constituent / usually / always / ever

melatonin

melanoma (type of skin cancer)