The most common and most likely answer to this crossword clue is the 6 letter word ONLINE
I've seen this crossword clue in Independent
O
N
L
I
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E
More clues leading to the result ONLINE
- Thrashing one-nil where Internet games are played
- Where to sign to be connected to network
- Net user is so like fish being played?
- Love new range of products available via internet
- Connected individual holding nothing back …
- Where bass could finally be connected?
- Status of well-connected surfer
- Connected to internet, single describes rejected love
- Surfing novice in ’09
- Surfing, maybe at equator
Buddy explains!

The straight part
We know that "available via internet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case available via internet = online.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 ONLINE mean?
ONLINE verb- To bring (a system, etc.) online; to promote to an active or running state.
- Of a system: connected (generally electrically) to a larger network.
- Available over, or delivered from, the Internet.
- Connected to the Internet.
- Available on a computer system, even if not networked.
- Of a system: active, particularly building facilities (such as power) or a factory or power plant.
- While online; while in a running or active state, or connected to the Internet.