Rare variant relating to or characteristic of something disastrous or ill-omened; having qualities of being unlucky or destructive.
Funest + -al. This appears to be a rare or constructed form attempting to add the -al suffix to funest to create an adjective form, though funest itself already functions as an adjective. This is not a standard or widely attested English word.
Words like 'funestal' reveal the hidden rules of English—while we can theoretically add -al to almost any noun, we rarely do, and when someone does it, it often sounds artificial or archaic, showing that language use is as much about 'what sounds right' to native speakers as it is about following rules.
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