absorption, acerbity, acid, acidity, acidulousness, acrimony, anger, animosity, asperity, assimilation, autacoid, bad humor, bad temper, biliousness, bitter resentment, bitterness, bitterness of spirit, causticity, chalone, choler, corrosiveness, digestion, digestive secretion, digestive system, discontent, endocrine, gall, gastric juice, gastrointestinal tract, gnashing of teeth, hard feelings, heartburning, hormone, ill humor, ill nature, ill temper, ingestion, intestinal juice, liver, mucus, pancreas, pancreatic digestion, pancreatic juice, predigestion, prostatic fluid, rancor, rankling, rheum, saliva, salivary digestion, salivary glands, salivary secretion, secondary digestion, semen, slow burn, soreness, sourness, sperm, spleen, tears, thyroxin, virulence