The most common and most likely answer to this crossword clue is the 7 letter word LINKAGE
I've seen this crossword clue in The Daily Telegraph
L
I
N
K
A
G
E
More clues leading to the result LINKAGE
- Part of mechanism leaking fluid
- Joint leaking badly
- A king involved in The French Connection
- Liquid leaking in connection
- Hook-up on singular golf course, apparently taking time
- Bond‘s occupation including killing and gadgets primarily
- Badly leaking connection
- Learner with printing requirement to get on connection
- Connection leaking out
- Nexus at border to smuggle silver following weekend
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 LINKAGE mean?
LINKAGE noun- A mechanical device that connects things.
- A connection or relation between things or ideas.
- The property of genes of being inherited together.
- A set of definitely related languages for which no proto-language can be derived, typically a group of languages within a family that have formed a sprachbund.