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Synonyms for Arrant (same or very similar meaning)

WordNet sense 1 (without qualification; used informally as (often pejorative) intensifiers):
complete, consummate, everlasting, gross, perfect, pure, stark, thoroughgoing, unadulterated, utter, double-dyed, sodding, staring, consummate, perfect

WordNet sense 2 (not diminished or moderated in intensity or severity; sometimes used as an intensifier):

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