How many letters does the top answer for “a message transmitted by telegraph” have?

The most common answer is telegram (8 letters).

Crossword clue: a message transmitted by telegraph

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

telegram 8 letters wn-def

a message transmitted by telegraph

a message transmitted by a heliograph. 50% similar → heliogram

a message transmitted by radiotelegraph. 50% similar → radiotelegram

of or relating to or transmitted by telegraph 50% similar → telegraphic