Call round to have drink of milk (7)

I believe the answer is:

lacteal

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'milk' is the definition.
(thesaurus)

'call round to have drink of' is the wordplay.
'round' is an anagram indicator.
'to have' means one lot of letters goes inside another.
'drink of' becomes 'tea' (I can't explain this - if you can you should give a lot more credence to this answer).
'call' anagrammed gives 'lacl'.
'lacl' enclosing 'tea' is 'LACTEAL'.

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(Other definitions for lacteal that I've seen before include "Milk-like; pertaining to milk" , "Milky resin" .)

I've seen this clue in The Daily Express.

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