"Overarm measurement" typically refers to a type of body measurement that is taken over the fullest part of the upper body, including the chest, shoulders, and back. It is often used in clothing or uniform fittings to determine the appropriate size for a garment that will fit comfortably and allow for a full range of motion.To take an overarm measurement, you would need to use a flexible tape measure and wrap it around the fullest part of the chest and shoulders while keeping the arms down by the sides. The tape measure should be snug but not tight, and it should be level and straight all the way around to get an accurate measurement.It's important to note that overarm measurement is just one of many measurements that may be taken to determine the correct size for a garment or uniform, and different manufacturers or brands may use different sizing charts or methods.