mawr
The Welsh word for great grandchildren is "awyrennau mawr."
Big, great, large
Mawr is the Welsh word for big or great eg Bryn mawr = big hill
Great > [Welsh] mawr
The Welsh word for Toxic is: Gwenwynig
The word 'fern' is not a Welsh word and has no meaning. The Welsh word for 'a fern' is 'rhedynen'.
The Welsh word for mum is mam.The Welsh word for dad is dad.
The Welsh word for Excellent is ardderchog, it is also the welsh for fantastic.
The Welsh word for 'decibel' is desibel.
The Welsh word for planet is 'planed' (plural - planedau)
The Welsh word for thunder is "taranu."
The Welsh word for 'rectangle' is petryal.