For engineering, lay a main central Tube (10,5)

I believe the answer is:

alimentary canal

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'tube' is the definition.
The answer and definition can be both body parts as well as being singular nouns.
Maybe they are linked in a way I don't understand?

'for engineering lay a main central' is the wordplay.
'for' becomes 'a' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'engineering' indicates an anagram (letters manipulated or engineered).
'lay'+'main'+'central'='laymaincentral'
'laymaincentral' is an anagram of 'limentarycanal'.
'a'+'limentarycanal'='ALIMENTARY CANAL'

Can you help me to learn more?

(Another definition for alimentary canal that I've seen is " gut".)

I've seen this clue in The Times.

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