Glossary of Yorkshirism
Clothead – stupid person
Words in Time and Place: Exploring Language Through the Historical Thesaurus of the Oxford English Dictionary
clot - A middle-class colloquialism for 'fool', but also found widely in dialects of northern England and Scotland in such forms as clothead and cloit, as well as in earlier 'blockhead' expressions as clotpoll (1609). It is often no more than a mild or friendly term of abuse, frequently with a nuance of clumsiness, as in the expression 'clumsy clot!'
Looking at clotpoll/clodpole:
Etymology
clod + pole (“head”)
and further clod
Etymology
From Middle English clod, a late by-form of clot, from Proto-West Germanic *klott (“mass, ball, clump”). Compare clot and cloud; cognate to Dutch klodde (“rag”) and kloot (“clod”).
Examples
Laughing Boy: The engrossing Yorkshire crime series
"What do you want?" Dave asked, one leg out of the door. "Um, so something fast." "Gazelle?" "No, clothead! Cheese, salad, whatever. Something that's ready made."
Yandro 184
I figure this must be deliberate humor; nobody could be that much of a clothead, so I smiled non-committally.
A Son of Hagar, by Sir Hall Caine
"He's allus stopping short too soon," said Gubblum. "My missis, she said
to me last back end, 'Gubblum,' she said, 'dusta mind as it's allus
summer when the cuckoo is in the garden?' 'That's what is is,' I said.
'Well,' she said, 'dusta not think it wad allus be summer if the cuckoo
could allus be kept here?' 'Maybe so,' I says; 'but easier said nor
done.' 'Shaf on you for a clothead!' says she; 'nowt so simple. When you
get the cuckoo into the garden, build a wall round and keep it in.' And
that's what I did; and I built it middling high, too, but it warn't high
enough, for, wad ye think it, one day I saw the cuckoo setting off, and
it just skimmed the top of that wall by a bare inch. Now, if I'd no'but
put another stone--"