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

Noun

In February 2020, a gas station in Boulder was not fined following a mix-up with its fuel transfers. —Jennifer McRae, CBS News, 9 Jan. 2026

One of his runs nearly contributed to a mix-up between William Saliba and David Raya, eventually leading to Bradley hitting the bar. —James McNicholas, New York Times, 8 Jan. 2026

Would the next Roberto Benigni podium-hurdle, envelope mix-up or even Slap have the same seismic cultural effect in a YouTube window? —Seth Abramovitch, HollywoodReporter, 7 Jan. 2026

Somehow a mix-up has occurred, perhaps even without their realizing it. —Judith Martin, Sun Sentinel, 6 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