WordNet sense 1 (ice crystals forming a white deposit (especially on objects outside)):

frost, hoarfrost, rime

WordNet sense 2 (showing characteristics of age, especially having grey or white hair):

gray, grey, grizzly, hoary, gray-haired, gray-headed, grey-haired, grey-headed, white-haired

WordNet sense 3 ((used especially of persons) having lived for a relatively long time or attained a specific age):

old