The most common and most likely answer to this crossword clue is the 12 letter word DEPARTMENTAL
I've seen this crossword clue in The Sunday Telegraph
D
E
P
A
R
T
M
E
N
T
A
L
More clues leading to the result DEPARTMENTAL
Buddy explains!
The straight part
We know that "Organised in units" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case organised in units = departmental.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 DEPARTMENTAL mean?
DEPARTMENTAL adjective- Of or pertaining to a department.