a dark scowl.
a false (or sour) note.
a glum, hopeless shrug.
a morose and unsociable manner.
a saturnine, almost misanthropic young genius.
a sour temper.
a sullen crowd.
he sat in moody silence.
her singing was off key.
sour milk.
The cream has turned--we have to throw it out.
The milk has soured.
the proverbially dour New England Puritan.
The wine worked.