Mate on train on about what Pine has on? (13)

I believe the answer is:

ornamentation

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'pine has on?' is the definition.
I can't tell whether this definition defines the answer.

'mate on train on about' is the wordplay.
'about' indicates anagramming the letters.
'mate'+'on'+'train'+'on'='mateontrainon'
'mateontrainon' anagrammed gives 'ORNAMENTATION'.

'what' is the link.

Can you help me to learn more?

(Other definitions for ornamentation that I've seen before include "Detailed artistic embellishment" , "Decorative work" , "Adornment" , "Decoration, embellishment" .)

I've seen this clue in The Times.

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