Definition of niggling for English Language Learners. : causing you to feel a slight pain or to be worried or annoyed for a long time.
What is PPAP? The Production Part Approval Process (PPAP) is a standardized process in the automotive and aerospace industries that helps manufacturers and suppliers communicate and approve production designs and processes before, during, and after manufacture.
BiPAP (also referred to as BPAP) stands for Bilevel Positive Airway Pressure, and is very similar in function and design to a CPAP machine (continuous positive airway pressure). Similar to a CPAP machine, A BiPAP machine is a non-invasive form of therapy for patients suffering from sleep apnea.