Bulimic treated over single or multiple depressions (8)

I believe the answer is:

umbilici

'multiple depressions' is the definition.
(an umbilicus is a navel)

'bulimic treated over single' is the wordplay.
'treated' indicates anagramming the letters.
'over' means one lot of letters goes inside another.
'single' becomes 'i' (one).
'bulimic' with letters rearranged gives 'umblici'.
'umblici' placed around 'i' is 'UMBILICI'.

'or' acts as a link.

(Another definition for umbilici that I've seen is " Cords can be cut".)

I've seen this clue in The Independent.

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