From Longman Dictionary of Contemporary Englishweek after weekweek after week (also week in week out) continuously for many weeks We do the same things week in week out. → week
Examples from the Corpus
week after week• We keep practicing the same dance steps week in, week out.• And this guy turns up, in Room 302, week after week after week.• But even though week after week the jokes were the same, we always laughed.• I understood how week after week he was all Clarisa needed.• Nicholas Church were occupied, week after week, by faithful Communists.• Not week after week, anyway.• The list will not be long because you tend to purchase the same food products week after week. 9. 