Trethias Island (EN) / Enys Tredhias (KW)

Parish: 
Hundred: 
Elements: 

dias

Meaning: 
Welsh dias 'fighting/battle'

enys

Meaning: 
island, isolated place

tre

Meaning: 
farmstead, settlement
Elements notes: 
enys 'island' + tre 'farmstead, settlement' + dias 'fighting/battle'