interj. [ Abbreviated from alackaday. ] Alack the day; alas; -- an expression of sorrow, regret, dissatisfaction, or surprise. [ 1913 Webster ]

interj. [ For alack the day. Cf. Lackaday. ] An exclamation expressing sorrow. [ 1913 Webster ]

☞ Shakespeare has “alack the day” and “alack the heavy day.” Compare “woe worth the day.” [ 1913 Webster ]