Definition of merse in English:

merse

(also mersk)

Pronunciation /məːs/

noun

dialect Scottish
  • Flat, alluvial, often marshy land beside a river, estuary, or the sea. Now chiefly: specifically partially reclaimed land bordering the Solway Firth.

Origin

Middle English. Variant of marsh; β. forms show regular loss of -k in final -sk.