NACK definitions

Nack

Nack (nak) is the 'Negative Acknowledge' character in many data codes; typically used to indicate receipt of a corrupted message, ordering retransmission.
Found on http://www.probertencyclopaedia.com/browse/GN.HTM

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NACK

Negative ACKnowledgement
Found on http://www.translationdirectory.com/glossaries/glossary117.htm

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