Antonyms for the word "more undernourished" include "well-nourished," "healthy," and "well-fed." These antonyms imply that the person or animal in question is receiving an adequate amount of nutrients and sustenance, indicating a positive state of health and well-being. Other antonyms for "undernourished" may include "nourished," "satiated," and "nurtured." These words suggest that the individual is receiving proper care and attention, and is not suffering the negative effects of malnutrition, starvation, or neglect. It is important to strive towards providing adequate nutrition and sustenance to all individuals, so that they can thrive and reach their full potential.