mix up

1 of 2

verb

mixed up; mixing up; mixes up

1

: to mistakenly think that (someone or something) is someone or something else : confuse

mixed the twins up

mixed up the times for the meetings

2

: to mistakenly put (something) in a place where something else should be

mixed up the two files

3

: to cause (someone) to be involved in a usually dangerous or improper activity

—usually used as (be/get) mixed up in

got mixed up in an illegal scheme

4

: to cause (someone) to become involved with usually bad or dangerous people

mix-up

2 of 2

noun

ˈmiks-ˌəp 

1

: a state or instance of confusion

a mix-up in our hotel reservations

2

: mixture

3

: conflict, fight

Synonyms of mix up

Noun

• mistake
• confusion
• foul-up

Examples of mix up in a Sentence

Noun

there was a mix-up at the airport and our luggage was accidentally sent to Ohio

Recent Examples on the Web

Verb

The two said a simple mistake on the second jump–mixing up which leg to grab– ended up costing them gold. —Kels Dayton, Hartford Courant, 5 Feb. 2026

McDonald-Foster likes to mix up her menu, including a recent addition of burgers for the first time in Crave Cafe's history. —Amanda Hancock, Louisville Courier Journal, 30 Jan. 2026

Noun

An Olympic official said there was a mix-up with Valieva's grandfather's heart medication. —Kiki Intarasuwan, CBS News, 6 Feb. 2026

Just last year, the Orlando Sentinel highlighted this systemic vulnerability through the harrowing story of a Georgia woman who unknowingly became a surrogate for another couple’s child after an embryo mix-up. —Robert Travieso, The Orlando Sentinel, 30 Jan. 2026

Word History

First Known Use

Noun

1841, in the meaning defined at sense 1

Kids Definition

mix-up

noun

ˈmik-ˌsəp

: an instance of confusion