ENGLISH
REFERENCE

fess up

phr. v..
B2 Upper Intermediate Oxford Informal

phr. v.. to admit that you did something wrong or made a mistake. You use this when you finally tell the truth about something you were hiding.

phr. v.. to confess or admit to a fault, error, or minor crime; marked informal register, often used in contexts involving social accountability or lighthearted interrogation.


SIMPLE

Come on, fess up—who ate the last cookie?

CONTEXTUAL

After the manager found the broken window, the new employee decided to fess up and apologize.

COMPLEX

Although he initially denied any involvement in the prank, he eventually had to fess up when the security footage was reviewed.

Origin

Clipping of confess up.

Particles
up
Separability
inseparable
Pattern
fess + up (+ to + object)
Usage

often used as an imperative or followed by the preposition 'to' and a noun or gerund.

Teaching tip

explain that 'fess' is a clipped form of 'confess'; highlight its informal nature compared to 'admit' or 'confess' to help students with register awareness.

Pitfall

He fessed up his mistake.He fessed up to his mistake.when mentioning the specific mistake, the preposition 'to' is required after the phrase.

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