Source : Webster's Revised Unabridged Dictionary (1913)

Puberulent \Pu*ber"u*lent\, a. [See {Pubis}.] (Bot.)
   Very minutely downy.

Source : WordNet®

puberulent
     adj : covered with fine soft hairs or down; "downy milkweed seeds"
           [syn: {downy}, {pubescent}, {sericeous}]