day of days (plural days of days) (idiomatic) A particularly noteworthy day; the day on which a milestone or especially memorable event occurs. quotations ▼ (Christianity, sometimes capitalized) Sunday, especially Easter Sunday.
day of days (plural days of days) (idiomatic) A particularly noteworthy day; the day on which a milestone or especially memorable event occurs. quotations ▼ (Christianity, sometimes capitalized) Sunday, especially Easter Sunday.