in English is:

intestacy

Mutations

Soft:ddiewyllysedd
Nasal:niewyllysedd
Aspirate:(no mutation)

Use

y diewyllysedd hwn
fy niewyllysedd i
dy ddiewyllysedd di
ei ddiewyllysedd ef/o
ei diewyllysedd hi
ein diewyllysedd ni
eich diewyllysedd chi
eu diewyllysedd nhw/hwy
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