The most common and most likely answer to this crossword clue is the 9 letter word INTERFACE
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result INTERFACE
- Worry about taking expert on in meeting
- Boundary fence rat ruined one must go over
- Meeting point for attack on Italian club
- Broadcast after nice connection between systems
- Worry about one on popular junction
- Painter facetiously assuming physical connection …
- Reconfigure a frenetic connection
- Bury’s features shared link
- A frenetic arrangement links man and machine
- Couple designing fine art near church
Buddy explains!

The straight part
We know that "physical connection …" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case physical connection … = interface.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 INTERFACE mean?
INTERFACE noun- The point of interconnection or contact between entities.
- A thin layer or boundary between different substances or two phases of a single substance.
- The point of interconnection between systems or subsystems.
- The connection between a user and a machine.
- The connection between parts of software.
- In object-oriented programming, a piece of code defining a set of operations that other code must implement.
- The internal surface of a coiled protein (compare exoface).
- To construct an interface for.
- To connect through an interface.
- To serve as an interface.
- To meet for discussion.