Other forms: supplemented; supplements; supplementing
A supplement is something added to something else. Nutritional supplements add vitamins and minerals to the ones already included in the food you eat.
If a zombie army wants to increase its ranks but is running out of bodies, it might supplement its troops with mummies. If the zombies put out their manifesto and then realize they left out an important point, they might supplement the manifesto with a press release. That press release could also be referred to as a supplement.
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