[{"Bold_text": "adjective", "List Items": ["noting or pertaining to a method of changing the frequency of an incoming radio signal by adding it to a signal generated within the receiver to produce fluctuations or beats of a frequency equal to the difference between the two signals."]}, {"Bold_text": "verb (used without object)", "List Items": ["to produce a heterodyne effect."]}, {"Bold_text": "verb (used with object)", "List Items": ["to mix (a frequency) with a different frequency so as to achieve a heterodyne effect."]}]