The term 'TELEGRAM Period' refers to the period of time in the late 19th and early 20th centuries when telegrams were the primary form of long-distance communication. During this period, telegrams were used to send messages quickly and efficiently over long distances. The term is derived from the word 'TELEGRAM, ' which is a message sent by telegraph. The crossword solution for this term is 'STOP, ' which is the signal used to indicate the end of a TELEGRAM transmission.