Dictionary / Vocabulary / 産毛
うぶげ
downy hair; down; vellus hair; peach fuzz
Also written うぶ毛、生毛
孵化後まもないヒナは、産毛が濡れていますが、２時間もすると乾いてフワフワになります。
The down of chicks that have just hatched is damp, but after two hours it dries out and becomes fluffy.