Lanugo

·noun The soft woolly hair which covers most parts of the mammal fetus, and in man is shed before or soon after birth.

lanugo
lānūgo, ĭnis, f. [cf. Gr. λάχνη, Lat. lāna], woolly substance, down, of plants, of the cheeks, etc. ...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.
lanugo
lānūgō īnis, f lana, woolly substance, down : flavens primā lanugine malas, V.: dubia, O.: tenera,...

An Elementary Latin Dictionary