Made illegitimate, impure, inferior, or corrupted; debased in quality or authenticity (British spelling).
Past tense and past participle of bastardise. The -ed ending marks this as a completed action, while -ise is the British English verb-forming suffix from Latin origins.
This adjective became common in describing corrupted texts and languages—scholars worried about 'bastardised' versions of classical works, showing how fears about purity extended from genealogy to literature.
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