pruinose
Concise Oxford English Dictionary © 2008 Oxford University Press:
pruinose /ˈpruːɪnəʊs, -z/
▶adjective chiefly Botany covered with white powdery granules; frosted in appearance.
– origin C19: from L. pruinosus, from pruina ‘hoar frost’.
'pruinose' also found in these Oxford entries:

