| selectivity [sǝ´lek`tiv·ǝd·ē] ANALYTICAL CHEMISTRY The ability of a type of method or instrumentation to respond to a specified substance or constituent and not to others. ELECTRONICS 1. The ability of a radio receiver to separate a desired signal frequency from other signal frequencies, some of which may differ only slightly from the desired value. 2. The inverse of the shape factor of a bandpass filter. |