Honeybee propolis is a brown or reddish resinous substance made by bees to protect the hive against animal and bacterial invaders. The word “propolis” is a compound of the Greek words “pro” and “polis” and translates to, “Before the city.” Bees use propolis as a building material to fill gaps and crevices, varnish combs and shape entrances, sometimes creating fantastic gobs that supposedly aid ventilation in the hive.