Crossword Genius

Moor steamship, possibly for alteration (13)

Ross

I believe the answer is:

metamorphosis

'alteration' is the definition.
(metamorphosis is a kind of alteration)

'moor steamship possibly' is the wordplay.
'possibly' is an anagram indicator.
'moor'+'steamship'='moorsteamship'
'moorsteamship' is an anagram of 'METAMORPHOSIS'.

'for' is the link.

(Other definitions for metamorphosis that I've seen before include "Total change in character" , "Complete change of appearance" , "Total change in form" , "Transmutation" , "Process of transformation" .)

I've seen this clue in The Telegraph.
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