an old chestnut

(old) chestnut

A topic, saying, or joke that has been repeated so much that it has become boring or irksome. Whether there's truth in it or not, I can't stand that old chestnut "follow your heart."
See also: chestnut
Farlex Dictionary of Idioms.

an old chestnut

or

a hoary old chestnut

mainly BRITISH
COMMON If you describe something that is said or written as an old chestnut or a hoary old chestnut, you mean that it has been repeated so often that it is no longer interesting. Finally, how do you answer that old interview chestnut: `Why should I hire you?' The film is based on the hoary old chestnut of good twin/bad twin, separated at birth, final fatal meeting — you get the idea.
See also: chestnut, old
Collins COBUILD Idioms Dictionary, 3rd ed.

an old chestnut

a joke, story, or subject that has become tedious and boring as a result of its age and constant repetition.
The most likely source for this sense of chestnut is in the following exchange between two characters, Zavior and Pablo, in William Dimond 's play Broken Sword ( 1816 ): ZAVIOR…When suddenly from the thick boughs of a cork tree— PABLO. (Jumping up) A chesnut, Captain, a chesnut…Captain, this is the twenty-seventh time I have heard you relate this story, and you invariably said, a chesnut, until now.
See also: chestnut, old
Farlex Partner Idioms Dictionary

an/that old ˈchestnut

(informal) a joke or story that has often been repeated and as a result is no longer amusing: ‘He told us all about the police arresting him for climbing into his own house.’ ‘Oh, no, not that old chestnut again.’
See also: chestnut, old, that
Farlex Partner Idioms Dictionary
See also:
  • (old) chestnut
  • chestnut
  • old chestnut
  • burg
  • blivit
  • a one-horse town
  • one-horse town
  • (one) could go (on) all day (about something)
  • live a dog's life
References in periodicals archive
AN OLD chestnut tree which was set to be felled to make way for a Tesco development has been granted a reprieve until further notice.
Tree row halted for time being
"sorry to bring up an old chestnut, but what's your take on spraying runner bean flowers with water?" asks Colin Cathcart, of Blackburn, Lancs A Old chestnuts are what keep gardeners going, Colin, so keep 'em coming.
"sorry to bring up an [...]; In the garden with Steve Riches OUR MAN with gReeN fiNgeRs
The message that appearance is less important than substance and loyalty is an old chestnut, but its treatment is cleverly done in this version.
Rabe, Jean. The Finest Creation
At the same time, that old favourite, despite being on the verge of becoming an old chestnut, education, education, education remains the key.
Here we go again
The Arsenal v Liverpool game also brings up an old chestnut of mine.
Letters: Home sides get the better deal from officials too
I KNOW it's an old chestnut that's always trotted out at this time of year, but...
James Whitaker Column: I'M NUTS ABOUT BALLET
I know it is an old chestnut but where is our 50-metre pool?
Helplessness over rising tax
The notion that affirmative action creates racism is an old chestnut; it has been applied to every initiative undertake in support of racial equality from teenth Amendment to the Brown decision and the 1964 Civil Rights Act.
Assault on affirmative action
This is an old chestnut known as the David Rhodes letter, which has resurfaced this summer and hundreds of you are asking us about it.
SORTED: RHODES TO RUIN