the.com/sourpuss

A face that filed a permanent complaint against joy.

means Someone with a habitually grumpy, sulky expression or disposition — a chronic malcontent in facial form.

from A straightforward compound from 'sour' (bitter, unpleasant in mood) plus 'puss,' old slang for 'face,' likely borrowed from the Irish word 'pus' meaning mouth or lip. The combination surfaced in American English in the early 20th century, giving a sour disposition a face to wear.

origin
sour plus puss, old slang for face
first recorded
1930s American slang
related term
puss comes from Irish word pus, lips
usage note
describes mood, not just expression
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