Stupid, slow-witted, or lacking sense and intelligence; appearing vacant or senseless.
From 'gorm' (to stare vacantly or lack sense) plus the suffix -less (without). Possibly Scandinavian origin, related to gaping or staring blankly without understanding.
This is a distinctly British insult that's surprisingly mild compared to American equivalents—it suggests someone is foolish in a harmless, vacant way rather than malicious, which says something about cultural attitudes toward stupidity.
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