Mysterious lace skirts handmade originally, in extra large (10)

I believe the answer is:

sphinxlike

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'mysterious lace skirts handmade originally in extra large' is the definition.
I can't tell whether this definition defines the answer.

'mysterious lace skirts handmade originally in extra large' is the wordplay.
'mysterious lace' becomes 'spike' (as in lacing or spiking food or drink. I am not sure about the 'mysterious' bit.).
'skirts' is an insertion indicator (skirt can mean to go around).
'originally' indicates taking the first letters.
'extra large' becomes 'XL' (abbreviation).
The initial letter of 'handmade' is 'h'.
'h'+'in'+'xl'='hinxl'
'spike' enclosing 'hinxl' is 'SPHINXLIKE'.

Can you help me to learn more?

(Another definition for sphinxlike that I've seen is " inscrutable".)

I've seen this clue in The Times.

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