The most common and most likely answer to this crossword clue is the 9 letter word HYPHENATE
I've seen this crossword clue in The Guardian
H
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More clues leading to the result HYPHENATE
- How to combine handles, for example, with short line
- Join up with the fellow, then yap freely inside
- Add dash to publicity about female artist on vacation
- Puff maintaining acceleration, then running round to put in a dash
- Transform an annoying person into a B-lister?
- Put in dash of neat rum husband found in promotion at first
- Dash it!
Buddy explains!
The straight part
We know that "put in a dash" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case put in a dash = hyphenate.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.
What does HYPHENATE mean?
HYPHENATE noun- A person with multiple duties or abilities, such as "writer-director", "actor-model", or "singer-songwriter".
- A person whose ethnicity is a multi-word hyphenated term, such as "African-American".
- To break a word at the end of a line according to the hyphenation rules by adding a hyphen on the end of the line.
- To join words or syllables with a hyphen.