pubescence
Botanical term for the fine, soft hairs on plant surfaces such as leaves and stems.
The leaves of this plant are densely covered with pubescence.
A baby's skin is covered with vellus hair.
Hair removal does not make vellus hair thicker.
villus
Compound of 軟 (nan, 'soft') and 毛 (mō, 'hair'). The reading is on'yomi, suggesting a Sino-Japanese origin, likely coined in medical or scientific contexts.