The most common and most likely answer to this crossword clue is the 10 letter word RHETORICAL
I've seen this crossword clue in The Times
R
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More clues leading to the result RHETORICAL
- Violently hector and rail in speech
- Response initially confused a clothier not expecting an answer?
- Choral rite oddly not expecting responses
- Over-elaborate start to reforms, ethical or otherwise
- Butler nearly fixed car with oil, with no need to answer
- Inflated the new ball Clair kicked around by river
- Curious rich lot are bombastic
- Verbose tale or rich fabrication
- Who cares, for example, about such questions?
- Unlimited short article reprinted and inflated
Buddy explains!

The straight part
We know that "n speech" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case n speech = rhetorical.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 RHETORICAL mean?
RHETORICAL adjective- Part of or similar to rhetoric, the use of language as a means to persuade.
- Not earnest, or presented only for the purpose of an argument.