Definition of "must"

(modal auxiliary, defective) 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.  quotations  examples

(modal auxiliary, defective) To do with certainty; indicates that the speaker is certain that the subject will have executed the predicate.  examples

(modal auxiliary, defective) Used to indicate that something is very likely, probable, or certain to be true.  examples

Something that is mandatory or required.  examples

The property of being stale or musty.  examples

Something that exhibits the property of being stale or musty.  examples

Fruit juice that will ferment or has fermented, usually from grapes.  quotations  examples

(transitive) To make musty.  examples

(intransitive) To become musty.  examples

Alternative form of musth  quotations  examples