恥垢 is read as ちこう (chikou) and means smegma.
ちこう
chikou
はじ
shame
はずかしい
disgraceful
はじる
to feel ashamed
ちじょく
disgrace
はじらう
to feel shy
はじしらず
shameless
はじさらし
はじらい
shyness
あか
account (e.g. for an online service)
むく
long kimono made from the same plain-coloured cloth
しこう
(dental) plaque
むち