Rat is struggling in narrow groove (5)

I believe the answer is:

stria

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'narrow groove' is the definition.
'stria' can be an answer for 'groove' (stria is a kind of groove). I am not sure about the 'narrow' bit.

'rat is struggling' is the wordplay.
'struggling' indicates an anagram.
'rat'+'is'='ratis'
'ratis' with letters rearranged gives 'STRIA'.

'in' is the link.

Can you help me to learn more?

(Other definitions for stria that I've seen before include "band" , "streak" , "Lines" .)

I've seen this clue in The Hindu.

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