Quintile Posted on 16th December 201510th May 2021 by ThePD (The Project Definition) Quintile manes any of five equal groups into which a population divide the total frequency into five equal parts. Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window) Related Posted in Business and tagged analysis. ThePD (The Project Definition) ThePD has been developing the Preferred Project Definitions based on the actual project execution and operation experiences and knowledge with the Project Language, and sharing with you daily basis.