A foolish or silly person; someone who talks nonsense or acts foolishly.
From Scottish dialect 'haver' (to talk foolishly) plus the suffix '-el'. Related to the verb meaning to waver or speak incoherently.
In Scottish insult hierarchy, calling someone a 'haverel' was midway between mild mockery and serious criticism—worse than saying they were confused, but not as bad as calling them outright stupid.
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