[I've now had it explained to me: Lem is the mutated version of Llym which means sharp or severe].
Sitting in the summit shelters we were reminded that carnedd means cairn as in burial and that Dafydd was the younger brother of (neighbouring Carnedd) Llywelyn, the last prince of an independent Wales. His daughter was Gwenllian and her name has now been given to what was previously called Carnedd Lladron or Carnedd Uchaf.
As we veered downwards Rob warned us to take care across this ‘scabreuse’ terrain – with a word like that I knew I was out walking with an international mountain leader. Definitely French and its English equivalent, scabrous, meaning ‘rough and covered with scabs’. Sort of appropriate for the bloody deaths of Llywelyn and Dafydd.