From HomoExcelsior

1. a message that was nonsense until decoded. 2. Subject matter, behavior, or language that is foolish or absurd. 3. a clown's exuberant nonsense. 4. a chatty letter full of gossip and nonsense. 5. wouldn't take any nonsense from the children. 6. A section within a strand of messenger RNA containing a nucleotide triplet that codes for no amino acid. Nonsense cannot be read during protein synthesis and so terminates the polypeptide chain.

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