Crossword Genius

Festival occurs for trades generally (10)

Ross

I believe the answer is:

easterlies

'trades generally' is the definition.
(as in trade winds)

'festival occurs' is the wordplay.
'festival' becomes 'easter' (Christian festival).
'occurs' becomes 'lies' (lying is a kind of occurring).
'easter'+'lies'='EASTERLIES'

'for' is the link.

I've seen this clue in The Guardian.
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