The word "phthisic" refers to a wasting away or deteriorating condition, especially of the body or mind. Synonyms for the term "more phthisic" include "more emaciated," "more skeletal," "more gaunt," "more haggard," "more wan," and "more wasted." Each of these terms describes a state of extreme thinness and depletion of energy or vitality. Other potential synonyms might include "more frail," "more fragile," "more delicate," or "more sickly," all of which suggest a state of weakness or vulnerability. Overall, these synonyms paint a picture of a person or thing that is struggling to maintain its strength and health.