The most common and most likely answer to this crossword clue is the 7 letter word MASONIC
I've seen this crossword clue in Financial Times
M
A
S
O
N
I
C
More clues leading to the result MASONIC
- . A prickly character chases Mike regarding order
- Brotherly love in man is awfully cold
- Mother hedgehog belonging to “boys only” club?
- Person in charge conceals note relating to secret order
- Like a lodge, with mum in charge protecting her boy
- Two generations in charge of secret society
- A faction of lamas on ice-skates, having something to do with a secret society
- Married a Seattle player involved with a fraternity
- Really excited about southern kind of temple
- Crazy hosts so like the Shriners
Buddy explains!

The straight part
We know that "Brotherly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case brotherly = masonic.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 MASONIC mean?
MASONIC adjective- Of or pertaining to stonemasons or masonry.
- Of or pertaining to freemasonry.