Nine months suggested, indeed (3)

I believe the answer is:

yea

'indeed' is the definition.
(I've seen this in another clue)

I cannot understand how the rest of the clue works.

(Other definitions for yea that I've seen before include "Verily" , "Affirmative, colloquially" , "Affirmative vote" , "Emphatic agreement" , "Archaic affirmative answer" .)

I've seen this clue in The Times.

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