Crossword Genius

Otherwise, can be made of tin (2,3)

Ross

I believe the answer is:

if not

'otherwise' is the definition.
(synonyms)

'made of tin' is the wordplay.
'made' is an anagram indicator.
'of'+'tin'='oftin'
'oftin' anagrammed gives 'IF NOT'.

'can be' acts as a link.

(Other definitions for if not that I've seen before include "Failing that" , "Unless" .)

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