noun
shaggy hair (of an animal)
Refers to long, rough, or unkempt hair on animals, especially dogs. Often used in the phrase むく毛の犬 (shaggy-haired dog).
あの犬はむく毛で、ブラッシングが大変だ。
That dog has shaggy hair and is hard to brush.
noun
Only when written 毳
Describes soft, fine, downy hair or fluff, such as on a chick or a peach. The kanji 毳 is specifically associated with this meaning, but it is very rare.
ひよこの毳はとても柔らかい。
The chick's downy feathers are very soft.
The word むくげ is a compound of むく (possibly related to むくむく, an onomatopoeia for something fluffy or shaggy) and 毛 (hair). The exact origin of むく is uncertain.