1. books containing systems of symbols, letters, or words used to represent other words or phrases for secrecy or brevity in communication
Usage: cryptography; telecommunications
2. reference books that provide standardized codes or classifications for data entry or analysis
Usage: data processing; statistics

Examples

• The military officers used codebooks to encrypt their secret messages.
• During wartime, codebooks were essential for secure communication between headquarters and field units.
• The telegraph company distributed codebooks to reduce the cost of long-distance messages.
• Medical researchers consulted codebooks to properly classify patient diagnoses.
• The survey team referenced their codebooks to ensure consistent data coding.
• Old naval codebooks are now displayed in the maritime museum.
• Statistical analysts rely on codebooks to interpret survey responses correctly.