something that has ceased to be useful or relevant.
beat / flog a dead horse, to persist in pursuing or trying to revive interest in a project or subject that has lost its usefulness or relevance.
So when the Today show staged a flash mob earlier this month, it had the effect of beating a dead horse.
Harlem Shake & All the Memes the ‘Today’ Show Killed (VIDEO) Kevin Fallon February 13, 2013
Nor is Cole worried that his party will be seen as whipping a dead horse to score cheap political points.
Obamacare 37, Republicans 0: House GOP Loses Again on Repeal Vote Michelle Cottle May 16, 2013
But, in a major way, harping on the sins of Arafat and Abbas is like flogging a dead horse.
A Response to Daniel Levy Benny Morris April 16, 2012
His recent plays, The God of Hell and Kicking a dead horse, had a vital political edge.
Sam Shepard Rides Again Caryn James January 29, 2010
The dead horse seemed to fill that whole side of the plaza and disturbed the bull-fighter.
The Blood of the Arena Vicente Blasco Ibez
There were two horses inside, but the dead horse blocked the door.
The Story of the Outlaw Emerson Hough
These accursed Navajos haven’t any scruple about stripping a dead horse.
Lone Pine R. B. (Richard Baxter) Townshend
A short time after this a cart with a dead horse in it passed our cab-stand.
Black Beauty Anna Sewell
The enemy succeeded in wounding a Bushman, who fell beneath his dead horse, and was there pinned.
South Africa and the Transvaal War, vol. 7 Louis Creswicke
Wherever he went, he met people who said to him, “Have you seen the dead horse?”
Changing Winds St. John G. Ervine
beat a dead horse, flog a dead horse
see: beat a dead horse
to make blissfully happy. Roman Catholic Church. to declare (a deceased person) to be among the blessed and thus entitled to specific religious honor. Contemporary Examples On that day, the family of a severely ill Costa Rican woman reportedly prayed to the beatified pontiff for her recovery. After Second Approved Miracle, Pope John Paul II […]
the act of a person or thing that beats, as to punish, clean, mix, etc.: Give the rug a good beating. a defeat or reverse; loss; setback: Several stocks took a beating in the market today. pulsation; throbbing: the beating of her heart. to strike violently or forcefully and repeatedly. to dash against: rain beating […]
most remarkable or unusual: This is the beatinest town I ever did see.
a severe thrashing administered for intimidation or revenge. Textiles. the process by which the loose pick is made an integral part of the woven material. Historical Examples In a two-hours’ beating-up the ravine he found no traces of bears. The Graysons Edward Eggleston