Concrete is securing link – these are the facts (9)

I believe the answer is:

realities

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'these are the facts' is the definition.
The definition suggests an adverb but the answer is not.

'concrete is securing link' is the wordplay.
'concrete' becomes 'real' (similar in meaning).
'securing' is an insertion indicator.
'link' becomes 'tie' (synonyms).
'is' enclosing 'tie' is 'ities'.
'real'+'ities'='REALITIES'

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(Other definitions for realities that I've seen before include "The facts of life" , "multiple universes" .)

I've seen this clue in The Guardian.

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