Polyphagic refers to an individual or animal that has a tremendous appetite and eats an excessive amount of food. Some synonyms for this word include gluttonous, ravenous, insatiable, hungry, and voracious. These terms indicate that the person or animal has an unquenchable appetite and desires to consume large quantities of food. Polyphagic can also be replaced with terms like greedy, piggy, or gourmand, which suggest that the person or animal is consuming more than they need and may be indulging in their eating habits. Regardless of the word you choose, it is clear that polyphagic behavior is characterized by a compulsion to eat and an inability to feel satiated despite consuming large quantities of food.