Y symudiad allweddol? Hwyl Llŷr From: Discussion of Welsh language technical terminology and vocabulary [mailto:[log in to unmask]] Ar ran/On Behalf Of Geraint Lovgreen Sent: 30 November 2011 18:20 To: [log in to unmask] Subject: crux (mynydda) Sef - Mountaineering the most difficult and often decisive part of a climb or pitch