Active vs. Nonactive: Active cannabinoids are non-acidic and used by the human brain/body. Activation occurs through heating (cooking, evaporation, smoking). Natural plant cannabinoids are acidic and need to be converted to their neutral form in order to be used by the human body. So one would know that fresh cannabis buds will mainly contain non-active cannabinoids. Processed ingredients should be more in active forms.
Absent cannabinoids: If a cannabinoid or terpene is empty, it is not necessarily absent but is below the limit of detection by the detector.