The most common and most likely answer to this crossword clue is the 5 plus 4 letter word MORSE CODE
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More clues leading to the result MORSE CODE
- Communication system that’s a bit dotty?
- Spooner’s unsophisticated method that allows transmission of messages
- Dashing chap uses it in messages
- Alphabet design recomposed after penny drops
- Sullen chief operator let out cipher used for communication
- Dashes to represent Tom in this?
- A venerable communication system, that’s the long and the short of it
Buddy explains!
The straight part
We know that "used for communication" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case used for communication = morse code.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.