Superlative form of 'gorsy'; most covered with gorse or having the greatest amount of gorse shrubs.
From 'gorsy' (covered with gorse) plus the superlative suffix -est, which marks the highest degree of the quality described.
The superlative -est ending is one of English's oldest features, used identically in Old English over 1,000 years ago, making 'gorsiest' part of an unbroken grammatical tradition.
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