The most common and most likely answer to this crossword clue is the 12 letter word INDENTATIONS
I've seen this crossword clue in The Daily Telegraph
I
N
D
E
N
T
A
T
I
O
N
S
Buddy explains!

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 INDENTATIONS mean?
INDENTATIONS noun- The act of indenting or state of being indented.
- A notch or recess, in the margin or border of anything
- A recess or sharp depression in any surface.
- The act of beginning a line or series of lines at a little distance within the flush line of the column or page, as in the common way of beginning the first line of a paragraph.
- A measure of the distance from the flush line
- A division unit of a piece of law distinguished by its indentation or by a dash