Given the task definition and input, reply with output. In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

Oxygen saturation or dissolved oxygen ( DO ) is a relative measure of the amount of oxygen that is dissolved in a given medium .

Oxygen saturation ( symbol S ) is a relative measure of the concentration of oxygen that is dissolved or carried in a given medium as a proportion of the maximal concentration that can be dissolved in that medium .