ENGLISH
REFERENCE

cock up

phr. v..
C1 Advanced Oxford Archaic Slang Vulgar

phr. v.. to do something very badly or make a big mistake. You use this when you fail at a task because of poor planning or a silly error.

phr. v.. to ruin or bungle a task through incompetence or carelessness; a transitive or intransitive phrasal verb used in British English with a highly informal, slightly vulgar register.


SIMPLE

I really cocked up that presentation today.

CONTEXTUAL

The organizers completely cocked up the seating arrangements, so half the guests had nowhere to sit.

COMPLEX

Despite months of meticulous preparation, the logistics team managed to cock up the entire operation within the first hour of the launch.

Origin

The first citation in the Oxford English Dictionary is from the Dictionary of Forces’ Slang (1948). The OED suggests that it derives ultimately from the noun cock, but gives no further detail. The nature of the earliest citation suggests that this expression entered the wider language from military slang, making etymologies from typesetting or archery (see below) seem unlikely. The term is sometimes attributed to the days of manual typesetting, when a letter that had become wedged slightly higher than the other letters on the line was said to be “cocked up”. Another claim relates to medieval archery. One of the three feathers on an arrow is a cock’s feather. If the arrow was incorrectly placed on the bow for drawing and release, the arrow would go off course because of the cock’s feather being up and therefore the arrow positioned wrongly on the bow. This was then known as a “cock up”.

Particles
up
Separability
optional
Pattern
cock + (object) + up
Usage

primarily British English and very informal; it can be used with or without an object.

Teaching tip

advise students that while common in the UK, it is borderline slang and may be considered mildly offensive or unprofessional in formal business settings.

Pitfall

He cocked it out.He cocked it up.the particle must be 'up'; 'cock up' is a fixed phrasal verb meaning to bungle.

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