An example of ail is for an older person to have poor health.
Origin of ailMiddle English eilen from Old English eglian, to afflict with dread, trouble from egle, harmful; akin to Gothic agls, infamous, Old Norse agi from source awe
verbailed, ail·ing, ails
Origin of ailMiddle English eilen from Old English eglian from egle troublesome
(comparative ailer or more ail, superlative ailest or most ail)
From Middle English eyle, eile, from Old English eġle (“hideous, loathsome, hateful, horrid, troublesome, grievous, painful”), from Proto-Germanic *agluz (“cumbersome, tedious, burdensome, tiresome”), from Proto-Indo-European *agʰlo-, *agʰ- (“offensive, disgusting, repulsive, hateful”). Cognate with Gothic (aglus, “hard, difficult”).
(third-person singular simple present ails, present participle ailing, simple past and past participle ailed)
From Old English eġlan, eġlian (“to trouble, afflict”), cognate with Gothic (agljan, “to distress”).
From Old English eġl.