A : a sign ♮ put on any degree on the musical staff to nullify the result of the preceding sharp or flat b : a Notice or tone influenced via the natural signal c. Biology Not generated or modified artificially; not conditioned: natural immunity; a natural reflex. tunes us/ˈnætʃ·ər·əl/ https://senior-dog-care74458.weblogco.com/37756843/dog-anxiety-relief-at-night-an-overview