Thank you both for your answers. I also thought it was Phthisis
but the spelling on this cert was very poor. I've seen the same cause of death on a few others certs I've got but never spelt quite so badly.
The term 'feebleness of heart
' is a new one on me though! My G x 3 grandmother Hannah had suffered so much sadness and tragedy in her life that I'm not surprised her heart was so weakened by all the upset
She did well to make it to 75!
Thanks again for your much appreciated input