in English is:

extremism

Mutations

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

Use

yr eithafiaeth hon
fy eithafiaeth i
dy eithafiaeth di
ei eithafiaeth ef/o
ei heithafiaeth hi
ein heithafiaeth ni
eich eithafiaeth chi
eu heithafiaeth nhw/hwy
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