# must

> English word · Verb · IPA /məst/ · frequency rank #198

## Definitions
1. To do as a requirement; indicates that the sentence subject is required as an imperative or directive to execute the sentence predicate, with failure to do so resulting in a failure or negative consequence.
2. To do with certainty; indicates that the speaker is certain that the subject will have executed the predicate.
3. Used to indicate that something is very likely, probable, or certain to be true.

## Etymology
From Middle English moste ("must", literally, "had to", the past tense of Middle English moten (“to have to”)), from Old English mōste (“had to”), 1st & 3rd person singular past tense of mōtan (“to be allowed, be able to, have the opportunity to, be compelled to, must, may”), from Proto-Germanic *mōtaną. Cognate with Dutch moest (“had to”), German musste (“had to”), Swedish måste (“must, have to, be obliged to”). More at mote.

## Easily confused with
- **mute** (https://plainspell.com/en/vs/must-vs-mute)
- **mutt** (https://plainspell.com/en/vs/must-vs-mutt)
- **musty** (https://plainspell.com/en/vs/must-vs-musty)
- **muster** (https://plainspell.com/en/vs/must-vs-muster)
- **MS** (https://plainspell.com/en/vs/ms-vs-must)
- **MT** (https://plainspell.com/en/vs/mt-vs-must)
- **mu** (https://plainspell.com/en/vs/mu-vs-must)
- **met** (https://plainspell.com/en/vs/met-vs-must)
- **Mrs** (https://plainspell.com/en/vs/mrs-vs-must)
- **mum** (https://plainspell.com/en/vs/mum-vs-must)
- **MPS** (https://plainspell.com/en/vs/mps-vs-must)
- **MUD** (https://plainspell.com/en/vs/mud-vs-must)
- **mat** (https://plainspell.com/en/vs/mat-vs-must)
- **mit** (https://plainspell.com/en/vs/mit-vs-must)
- **mug** (https://plainspell.com/en/vs/mug-vs-must)
- **MoS** (https://plainspell.com/en/vs/mos-vs-must)
- **MSM** (https://plainspell.com/en/vs/msm-vs-must)
- **MSG** (https://plainspell.com/en/vs/msg-vs-must)
- **mot** (https://plainspell.com/en/vs/mot-vs-must)
- **MSP** (https://plainspell.com/en/vs/msp-vs-must)

## Common misspellings (6)
`mmust`, `msut`, `musst`, `mustt`, `muts`, `umst`

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/must