The morphological nature of the edible part of coconut is

The edible part of coconut is endosperm. Coconut water is free nuclear endosperm and the white kernel is the cellular endosperm.

Initially, the coconut is a nuclear liquid endosperm. it is a coenocytic liquid tissue with lots of rapidly dividing nuclei. At some point, gelification of the soil surrounding the nuclei occurs and cellular boundaries start to appear. These cells and nuclei start to settle down on the endothelium (inner lining of the integuments) and the cells divide to produce a columnar sort of a covering over it. This is what forms the characteristic of coconut meat. Development of the cellular endosperm is by coalescence of these deposited cells and nuclei at the antipodal end and continues towards the top. The cells right above the endothelium stay meristematic for a long time while the columnar cells on top of this meristematic layer grow radially inward.