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.
CPAP, or continuous positive airway pressure, is a treatment that uses mild air pressure to keep the airways open. CPAP typically is used by people who have breathing problems, such as sleep apnea. CPAP also may be used to treat preterm infants whose lungs have not fully developed.