the thin edge of the wedge

the thin edge of the wedge

Some minor change or development that instigates or foreshadows something much larger or more impactful. Typically used in reference to that which will lead to an unfortunate, undesirable, or catastrophic outcome. These new driverless cars are just the thin edge of the wedge, if you ask me—pretty soon, every facet of our lives will be controlled by robots and automation! If we allow them to get a foothold in this territory, it could be the thin edge of the wedge that sees them stealing huge portions of our market share.
See also: edge, of, thin, wedge
Farlex Dictionary of Idioms.

thin edge of the wedge

A minor change that begins a major development, especially an undesirable one. For example, First they asked me to postpone my vacation for a week, and then for a month; it's the thin edge of the wedge and pretty soon it'll be a year . This term alludes to the narrow wedge inserted into a log for splitting wood. [Mid-1800s]
See also: edge, of, thin, wedge
The American Heritage® Dictionary of Idioms by Christine Ammer.

thin edge of the wedge, the

An unimportant action that is the start of a major development, often an undesirable one. This expression alludes to the pointed metal wedge inserted into a log for splitting wood. The expression began to be used figuratively in the nineteenth century. Anthony Trollope used it several times in Dr. Thorne (1858), and it was commonplace by the end of the century. Richard Blackmore had it in The Remarkable History of Sir Thomas Upmore (1884): “My father kept calling him . . . the thin edge of the wedge, and telling dear mother . . . not to let him in.”
See also: edge, of, thin
The Dictionary of Clichés by Christine Ammer
See also:
  • thin edge of the wedge
  • thin edge of the wedge, the
  • light the (blue) touch paper
  • light the blue touch paper
  • light the fuse
  • pause for effect
  • winged words
  • keel over
  • buck the trend
  • any (one) worth (one's) salt
References in classic literature
Eager objected, saying that here was the thin edge of the wedge, and one must guard against imposition.
A Room With A View
It should be called in by the Welsh Government and thoroughly scrutinised, otherwise this will be the thin edge of the wedge, leaving our communities wide open to other rapacious and cynical developments which do nothing to strengthen and benefit our city and its residents.
South Wales Echo letters: Saturday, July 6, 2019; Your letters to the South Wales Echo
This is the thin edge of the wedge which is likely to continue."
Student high-rise dubbed 'Cardiff 's ugliest building'
Many rural organisations fear NRW's ban on pheasant shooting on public land is the thin edge of the wedge. In reality, most shooting in Wales takes place on private land and an Act of Parliament would be required to curtail the sport.
BAN PHEASANT SHOOTING ON YOUR LAND; University urged to follow lead set by the NRW
But to be sustainable as a restaurant it should use the crabs (and it's Asia's 50 Best recognition) as the thin edge of the wedge in introducing the world to Sri Lankan cuisine, rather than offering drearily familiar fillers on the bottom half of the menu.
The upmarket crustacean experience
All this is just the thin edge of the wedge. The Saudi-led war on Yemen is the latest manifestation of Arab interventionism, a trend that has been gaining momentum in the Middle East since the Saudi intervention in Bahrain during the Arab uprisings.
Saudi Petro-Dollars Keep Washington at War in Yemen
"We are getting the thin edge of the wedge and being penalised.
It's ref justice as Stoke pay penalty again; everton 1 stoke 0
Developers and speculators are waiting to move in, so whatever the decision is, let's hope that from Castle Hill one does not see only new developments and that this is not the thin edge of the wedge or detrimental to our 'Summer Wine' country.
What about Castle Hill? FEEDBACK
Even at the thin edge of the wedge, the Pacman will take home PS50million, Mayweather a smoking PS78m.
Keep those eyes on the PRIZECARL ..and you can Av a crack at real glory
It would, in my view, be the thin edge of the wedge to allow people to cash in on this kind of asset to the detriment of green space.
Red light for greenbelt bid
At the thin edge of the wedge there is almost no retardation.
Mechanism of abrasion resistance II: research shows PTFE film serves as the nucleation site for the crystallization of wax
Hughes has enjoyed success at Falkirk and in his short spell at Livingston but suffered the thin edge of the wedge at his beloved Hibs and more recently at Hartlepool.
Did I miss game? Do Yogi Bears s*** in the woods?
"Let's see if the company are prepared to step back from the brink - or will they try to impose further conditions?" Molly Bogle added: "The thin edge of the wedge springs to mind."
I switched jobs to secure my family's future .. now this
But any move towards state regulation would be the thin edge of the wedge.
A free Press protects all our freedoms; VOICE OF THE voice@sundaymirror.co.uk
I wrote there that, "in deciding most matters on behalf of the shareholders, incumbent directors are supposed to act less like Representatives (reflecting the current desires of their local constituencies) and more like Senators (considering broader interests)." To similar effect was the analysis four years later in my column "The Thin Edge of the Wedge" [3Q 2007]: (a) "Shareholders do not govern directly; they elect directors to perform that role" and (b) in a world of shareholder rule by plebiscite, "governance chaos would prevail."
Sideshows of the main event: what the fight, at heart, has been about