drive a wedge between (someone or something)

To cause discord between two people or things. I used to be close friends with Tiffany, but once she started dating my ex-boyfriend, it really drove a wedge between us. No, I don't see my parents much. There's just a ton of issues that have driven a wedge between us over the years. I would never say something like that about you! Al just wants to drive a wedge between us—don't listen to him!

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.

the thin end of the wedge

The inconspicuous beginning or initial stage of something that will be unfavorable, cause problems, or bring decline. Primarily heard in UK, Australia. This law is the thin edge of the wedge. If it's passed, you can expect more extreme legislation to follow.

See also: end, of, thin, wedge

wedge between (someone or something)

1. To become lodged, jammed, or stuck in a tight space between two people or things. The ball had wedged between two branches at the top of the tree, so there was no way to get it down. Some jerk wedged between me and my girlfriend and just stayed stuck there for the whole concert.

2. To jam or lodge someone or something in a tight space between two people or things. A noun or pronoun is used between "wedge" and "between"; often used in passive constructions. The table kept wobbling, so I wedged a napkin into the gap between the floor and one of the legs. I was wedged between Bill and Steve for the entire bus ride home.

wedge in

1. To become lodged, jammed, or stuck into some tight space. I thought the car would fit, but it ended up wedging in the narrow alleyway. The fabric got caught on the machinery and wedged in.

2. To jam or lodge someone or something into some tight space. A noun or pronoun can be used between "wedge" and "in"; often used in passive constructions. The table kept wobbling, so I wedged in a napkin under one of the legs. I was wedged in my seat for the entire performance. She wedged her hand in the opening to stop the leak.

wedge into (something)

1. To become lodged, jammed, or stuck into some tight space. I thought the car would fit, but it ended up wedging into the narrow alleyway. The fabric got caught on the machinery and wedged into the gears.

2. To jam or lodge someone or something into some tight space. A noun or pronoun is used between "wedge" and "in"; often used in passive constructions. The table kept wobbling, so I wedged a napkin into the gap underneath one of the legs. I was wedged into my seat for the entire performance. She wedged her hand into the opening to stop the leak.

drive a wedge between

someone and someone else Fig. to cause people to oppose one another or turn against one another. The argument drove a wedge between Mike and his father.

wedge someone or something (in) between people or things

to work someone or something into a tiny space between people or things. The usher wedged us in between two enormously fat people, and we were all very uncomfortable. They wedged in the package between Jane and the wall. We had to wedge Timmy between Jed and the side of the car.

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]

drive a wedge between someone and someone

COMMON If someone or something drives a wedge between people who are close, they cause bad feelings between them and this causes the relationship to fail. This was all part of his plan to separate me from my daughter and drive a wedge between us. His aim was to destabilize the country by driving a wedge between the people and their government.

See also: and, between, drive, someone, wedge

the thin end of the wedge

BRITISH

The thin end of the wedge is the beginning of something bad which seems harmless or unimportant at present but is likely to become much worse in the future. I think it's the thin end of the wedge when you have armed police permanently on patrol round a city. This decision could prove to be the thin end of the wedge towards making the 1.68 inch ball the legal ball the world over.

See also: end, of, thin, wedge

Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012

the thin end of the wedge

an action or procedure of little importance in itself, but which is likely to lead to more serious developments. informal

See also: end, of, thin, wedge

drive a wedge between A and B

make two people become less friendly or loving towards each other: The disagreements over money finally drove a wedge between them, and they ended up getting divorced.

A wedge is a piece of wood, metal, etc. with one thick end and one thin pointed end that you use to keep two things apart or to split wood or rock.

the thin ˌend of the ˈwedge

(especially British English) used for saying that you fear that one small request, order, action, etc. is only the beginning of something larger and more serious or harmful: The government says it only wants to privatize one or two railway lines, but I think it’s the thin end of the wedge. They’ll all be privatized soon.

A wedge is a piece of wood, metal, etc. with one thick end and one thin pointed end that you use to keep two things apart or to split wood or rock.

See also: end, of, thin, wedge

wedge in

To lodge or jam something or someone in some location: I accidently wedged my hat in the flue. The box was wedged in the crawl space.

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.”