Liquid via runnel to arm carrier? (5,4)

I believe the answer is:

ulnar vein

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'arm carrier?' is the definition.
The definition and answer can be both body parts as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'liquid via runnel' is the wordplay.
'liquid' indicates anagramming the letters.
'via'+'runnel'='viarunnel'
'viarunnel' with letters rearranged gives 'ULNAR VEIN'.

'to' is the link.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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