One repeatedly has trapped gas? (4)

I believe the answer is:

neon

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'trapped gas?' is the definition.
'neon' can be an answer for 'gas?' (I've seen this before). I am not sure about the 'trapped' bit.

'one repeatedly has' is the wordplay.
'one repeatedly' means two replacements for 'one'.
'has' indicates a hidden word.
'NEON' is hidden in the letters of 'one one'.

Can you help me to learn more?

(Other definitions for neon that I've seen before include "One of the six inert gasses" , "Element 10, used in lights" , "None (anag.)" , "Colourless noble gas" , "Gas used in fluorescent lamps" .)

I've seen this clue in The Independent.

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