Said why Heather's clothing is not straight (5)

I believe the answer is:

lying

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'is not straight' is the definition.
(I've seen this before)

'said why heather's clothing' is the wordplay.
'said why' becomes 'y' (I am not sure about the 'said' bit.).
'heather' becomes 'ling' (synonyms).
'clothing' indicates putting letters inside (some letters cover up or clothe others).
'y' going inside 'ling' is 'LYING'.

Can you help me to learn more?

(Other definitions for lying that I've seen before include "Prone - mendacity" , "Prone - untruthful" , "Deceitful" , "Perjury" , "retailing pork pies" .)

I've seen this clue in The Times.

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