From: dgkilday57
Message: 71085
Date: 2013-03-14
>The early sense of _cossus_ was probably 'segmented worm, cutworm'. The collocation _vermis cossus_ likely led to the metaplastic form _cossis_ (Plin. etc.). At any rate the priority of the /o/-stem is shown by the antiquity of the cognomen Cossus in the annals. In more recent times, Dennis Rodman was nicknamed "the Worm".
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> I was wrong about the 'whet' root. It is not quasi-Narten but an ordinary ablauting root *k^weh1d- (ON _hva:ta_, etc.), *k^woh1d- (Go. _hwo:ta_, etc.), *k^w&1d- (Lat. _quadrum_, OE _hwaet_, etc.).
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> I believe Lat. _triquetrus_ belongs to a different root *kWet- found also in _cossus_ 'worm', the latter from *kWot-to-. It cannot be from *kWod-to- because Lachmann's Law would have given Lat. *co:ssus, which would have undergone regular post-long degemination to *co:sus, like _caussa_ to _causa_.
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