The relaxed form of DNA in a cell's nucleus is called chromatin.
<h3>CHROMATIN:</h3>
Chromatin is a complex of DNA and histone proteins within the cell's nucleus. The DNA is too long to fit into the cell's nucleus, hence, is coiled around proteins called histones.
This complex forms the structure called chromatin, which then condenses during the prophase stage of cell division to form a more compact structure called chromosome.
Therefore, it can be said that the relaxed or uncondensed form of DNA in the nucleus of a cell is called chromatin.