Death

"A point of irreversible seizure of all physio-biochemical processes." Pandey, Shiv Shanker, Rohit Bhatt, and Budhi Sagar Tiwari. ‘Plant Death: Short and Long Life Span to Immortality’. In Sensory Biology of Plants, edited by Sudhir K. Sopory, 601–20, 2019.

“The permanent cessation of functioning of the organism as a whole.” (the problem here is that it is hard to define what an organism is and also that its organs or cells might die)

Culver, Charles M., and Bernard Gert. Philosophy in Medicine: Conceptual and Ethical Issues in Medicine and Psychiatry. New York: Oxford University Press, 1982.

Programmed cell death or apoptosis.

Some flowering plants can control when they die to aid procreation.

Miryeganeh, Matin. ‘Senescence: The Compromised Time of Death That Plants May Call on Themselves’. Genes 12, no. 2 (2021): 143. https://doi.org/10/gsmt88.

Aging and Senescence

This article also discusses and 'immortal' jellyfish.

Miller Jr, William B., František Baluška, Arthur S. Reber, and Predrag Slijepčević. ‘Why Death and Aging ? All Memories Are Imperfect’. Progress in Biophysics and Molecular Biology 187 (2024): 21–35. https://doi.org/10/gtg5rs.