The most common and most likely answer to this crossword clue is the 6 letter word SERMON
I've seen this crossword clue in The Guardian
S
E
R
M
O
N
More clues leading to the result SERMON
- Address hesitation by maiden hugged by boy
- Son has more fancy new address
- Address given weekly in advertiser monotonously
- Hesitation married son deviously hides in discourse
- Address in Rome’s surprisingly close to Vatican
- Address delivered by wiser Monsignor
- Address child about school period head left
- Service lecture
- Morse upset by new lecture
- Some random oration, all empty talk
Buddy explains!

The straight part
We know that "discourse" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case discourse = sermon.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 SERMON mean?
SERMON noun- Religious discourse; a written or spoken address on a religious or moral matter.
- A lengthy speech of reproval.
- To discourse to or of, as in a sermon.
- To tutor; to lecture.