Ail/eɪl/ Definition 1 of 2Pro Tip 1/3Health Context Used when describing someone's health condition, mostly in a negative sense. After the surgery, he seemed to ail more than before. Pro Tip 2/3Longevity Issues Often related to long-lasting health problems rather than temporary sickness. Her grandmother ailed with arthritis for many years. Pro Tip 3/3Emotional Weight Can imply a worrying or empathetic tone when discussing health. It's clear the constant pain is ailing him deeply.