An extremely archaic term, possibly the adjectival form of 'forinsec,' relating to external or foreign matters, likely used in medieval legal contexts.
From Latin 'foris' (outside, foreign) with English adjectival suffix '-al.' This word is exceptionally rare and may appear in only a handful of medieval manuscripts.
When you see words ending in '-secal' that nobody's heard of, you're probably looking at a Latin legal term that was tried once in English, found too weird, and abandoned—linguistic evolution in real time.
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