Time to muse (5)

I believe the answer is:

erato

'muse' is the definition.
(I know that Erato is a muse)

'time to' is the wordplay.
'time' becomes 'era' (era is a kind of time).
'era'+'to'='ERATO'

(Other definitions for erato that I've seen before include "Muse of lyric love-poetry" , "inspiration for poetry" , "Poet's inspiration" , "Source of artistic inspiration" , "Lyric poetry's muse" .)

I've seen this clue in The Telegraph, The Globe and Mail and The Times.

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