To affect with pain or uneasiness, either physical or mental; to trouble; to be the matter with; used to express some uneasiness or affection, whose cause is unknown; as, what ails the man? I know not what ails him
If something ails a group or area of activity, it is a problem or source of trouble for that group or for people involved in that activity. A full-scale debate is under way on what ails the industry. To cause physical or mental pain or uneasiness to; trouble. See Synonyms at trouble
To be affected with pain or uneasiness of any sort; to be ill or indisposed or in trouble
somewhat ill or prone to illness; "my poor ailing grandmother"; "feeling a bit indisposed today"; "you look a little peaked"; "feeling poorly"; "a sickly child"; "is unwell and can't come to work