The most common and most likely answer to this crossword clue is the 8 letter word WIRELESS
I've seen this crossword clue in Independent
W
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L
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More clues leading to the result WIRELESS
Buddy explains!

The straight part
We know that "lacking connection" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case lacking connection = wireless.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 WIRELESS mean?
WIRELESS noun- The medium of radio communication.
- Wireless connectivity to a computer network.
- A radio set.
- To send a message by wireless (by radio)
- Not having any wires.
- Of or relating to communication without a wired connection, such as by radio waves.