Torridonian
Concise Oxford English Dictionary © 2008 Oxford University Press:
Torridonian /ˌtɒrɪˈdəʊnɪən/
▶adjective Geology of or denoting the later stage of the Proterozoic aeon in NW Scotland, from about 1,100 to 600 million years ago.
'Torridonian' also found in these Oxford entries:

